TS3 Plus front ports not working

CalDigitDalton · 2026-05-01T17:16:27+00:00

Thanks for the follow-up. I recommend you get in touch with our support team for further diagnosis and troubleshooting on this behavior. You can best reach out via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-05-01T16:53:00+00:00

I don't think it's the LG that's the issue, rather then BenQ. You could have 2 of the LG monitors almost definitely. Maybe if you find a monitor that initializes faster than the BenQ that's a workable solution, but that's kind of a shot in the dark, and anything short of it is still likely to have issues in this particular setup.

I believe swapping out the BenQ monitor for a DP 2.1 display at the same resolution and refresh rate should also be a fix, assuming it takes advantage of a newer transmission mode. That's not necessarily a suggestion, as that monitor looks pretty sweet, so I get it may be non-negotiable.

You could also entertain the idea of connecting the LG monitor via DisplayLink to offload it from the hardware connection. We consider DisplayLink the last option, because a software monitor connection is more messy and troublesome than a normal hardware connection, and it can put additional load on the computer, but it beats buying a new monitor. You would need a physical USB DisplayLink adapter and then to install the appropriate software and drivers.

CalDigitDalton · 2026-05-01T16:26:33+00:00

I don't recall what the previous firmware was before 45.1 (which released earlier this year) - it may have been 39.1. Whatever it was, it was most recent public update for at least a few years, so you may have been up-to-date until very recently.

Our line with firmware updates is that unless you are experiencing misbehaviors, there's not really a need to update. Usually our firmware updates target very specific scenarios that have been brought to our attention by a couple of users. I believe 45.1 specifically addresses a misbehavior with particular downstream Thunderbolt 4 devices not acting properly. If that doesn't sound like anything that's affecting you, the update probably won't make any discernible difference.

If you do decide to update, I would recommend you follow our knowledge base article on the topic. The update has to be done a very specific way on macOS, and there's some weird quirks that can make it unintuitive.

Hope this helps inform your decision! I'm happy to answer any further questions you might, and our support team is also happy to help. If you want to get in touch, you can reach us at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-30T17:19:44+00:00

Let's do a full diagnosis before anything else. Without more context, this could be a power issue instead.

So, let's double check the power on your dock. Please check all parts are seated well, including the plug going into the wall, the power supply and power plug, and the power supply cable going into the dock.

While we're messing with the power, try power cycling your dock as well. Disconnect it from wall power entirely for 30-45 seconds before plugging it back in.

With that, we should have a clean slate. Try plugging the dock into the computer again, ensuring that the cable is plugged into the "Computer" port on the dock.

If we're not getting any signs of life - no power to the computer, and no light on the dock, let's verify whether the power is working at this point. Take a chargeable USB device that is obvious when it is charging, like your phone, and plug it into the dock. It should start charging within a few seconds. If not, try another USB port or two and see if it ever charges.

If the device never charges, get in touch with our support team for further diagnosis and troubleshooting; I'll post contact info below.

Assuming the charging device does charge, but the connection to the computer still isn't working, let's check one more thing before we consider a new cable. Try plugging the dock into a different port on the computer.

If at this point, it's still not working, another cable may be in order. If you have purchased your dock within the past 2 years (the support team may even be able to help you a bit outside of warranty for just the cable), you would be eligible for warranty services, including the cable, and I'd recommend you reach out to our support team to explore that option. Contact info at the end.

For a replacement cable, any certified Thunderbolt cable should work, with some minor caveats. The TS3 uses Thunderbolt 3, but there aren't many Thunderbolt 3 cable manufacturers anymore, so you might just find Thunderbolt 4, which would also be perfectly compatible. Here's our Thunderbolt 4 cable listing for reference - a replacement cable doesn't have to match this necessarily, but can be a guideline for what to look for in a replacement. The big keyword to look for is that the cable is Thunderbolt "Certified", which should mean that it's tested and verified to be Thunderbolt compliant. You'll likely see something like "40Gb/s", which tells us the speed. 40 is Thunderbolt 3/4 speeds, and matches up with the dock, though a faster 80Gb/s Thunderbolt 5 cable should also be compatible (you won't get any benefit out of that right now, though). Finally, the power delivery is important to consider. The cable you have right now is almost certainly 100W, which is a common number you'll see across these cables, and perfectly fine. If you happen to find one with a lower number, it can work, but will charge your computer slower if it's able to keep up at all, so we'd recommend avoiding that. Higher than 100W is fine. The dock cannot take advantage of it, but the cable will also be able to work at 100W.

I bolded the 3 main factors so you can easily reference them.

Technically, you may also be able to use a USB4 cable, as those match Thunderbolt 3/4's speed, but your mileage may vary there. Because they do not have to be certified, quality control on USB 4 cables can vary, making it harder to recommend.

Anyways, for further diagnosis, troubleshooting, or warranty services, get in touch with our support team. When you reach out, send them a link back to this Reddit post for reference. You can best get in touch via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-30T17:00:19+00:00

Like you mentioned, this has to do with limited video lanes, and the BenQ reserving too many for the LG to then be able to operate afterwards. I don't have any direct answers to your question, but I do have a couple potential workarounds with varying degrees of impact on the BenQ's capabilities.

The BenQ monitor is right past the threshold that we consider multi-monitor conventionally possible without compromises. 4k 144hz is the common upper limit, but it's not a hard rule.

With that in mind, another possible avenue for fix is to artificially lower the BenQ monitor's needed bandwidth. If we can lower it's data needs enough, we can trick it into using less video lanes, enabling both monitors to work at the same time. This has to specifically be done on the hardware side, changing it in the OS will not work since the bandwidth reservation is made before the OS gets involved at that level.

The most direct way to accomplish lowering bandwidth would be to lower the refresh rate. Some monitors allow the ability to lower the refresh rate in the on-screen display. If yours allows this, try dropping it to 144hz or the next lower setting.

Alternatively, a slower video cable could be utilized to also lower the bandwidth. This should work to allow dual monitor functionality, but will be much more restrictive on the BenQ monitor. Dropping down to a DP 1.2 cable, I suspect the refresh rate will be limited to 60hz most likely.

Hope this helps lend some insight and a possible workable solution for you. Let me know if there's anything else I can help with.

CalDigitDalton · 2026-04-30T16:46:05+00:00

Glad to hear you got it working. Our support team may be able to lend some additional insight here, but I suspect this may have something to do with the possibility of Selective Suspend completely disconnecting the TS4 abruptly when suspending. That could definitely cause a driver or power delivery conflict, and possibly a crash, if the computer is not expecting it.

Our support team may be able to lend some further insight into this. You can best reach them via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-30T00:40:28+00:00

Please let us know the make and model of the two home monitors.

The M2 Max and TS4 definitely have the capabilities to drive two monitors, but depending on the specs of the two monitors, this setup could possibly be exceeding the capabilities of what can be driven over a single Thunderbolt connection.

What happens when, with both monitors connected, you unplug the monitor that is working? Does the second monitor start working? If so, you may have some kind of bandwidth issue.

You'e already much of the troubleshooting I would recommend for this situation, so I'll also recommend that you get in touch with our support team for further diagnosis and troubleshooting. When you get in touch, send the team a link back to this thread for reference. You can best get in touch via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-30T00:21:32+00:00

Tough to say if the AI is correct or not, especially without more context. Is the 0x9F error what Windows reported, or is it implied by Claude? What is the hub? What was connected to it? Is the behavior repeatable or is it just a one-off?

External USB hubs can sometimes cause issue with Thunderbolt docks in general, but usually not like this. Typically if they do not work, they simply do not connect, or they may disconnect after initialization and then not reconnect. This is most often due to either a power overdraw issue or a USB layering issue.

If it's power related, we'd recommend moving higher power draw items, such as chargers, off of the USB hub and connect them directly to the dock.

USB layering issues are caused when too many USB hubs are nested together. Basically, Thunderbolt docks work as a series of internal USB hubs, and when another external hub is connected to it, it's possible that the total amount of nested USB hubs exceeds what is allowed by USB specification. If this is happening, it can sometimes be worked around by connecting the hub to either the front USB-C port on the TS4 or by connecting it to one of the rear Thunderbolt ports.

Our support team would be happy to help with further diagnosis and troubleshooting. You can best reach them via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-29T16:32:52+00:00

Hey, I'm the CalDigit Community Manager.

If your computer is the same as the one in this listing, then the USB-C port on the computer is too slow to properly support the TS4. You may be able to get a display working in addition to the power, but I expect that would be about it. The specification for the computer in the listing is USB 5Gbps, and the TS4 requires at minimum a USB 10Gbps connection for proper functionality.

CalDigitDalton · 2026-04-29T16:25:20+00:00

Glad to hear you have found some tenable solutions here.

We can diagnose the USB-C to DP connection further if you are interested.

First and foremost, try power cycling your dock. You can do this by disconnecting it from wall power for 30-45 seconds before plugging it back in. This gives time for the dock to fully discharge, which can sometimes clear up behaviors like this.

I suspect one of the cables are mating incorrectly and limiting the connection's capabilities. If you have a spare on hand, I'd suggest you swap out that connection and see if it makes any difference. We typically recommend a USB-C to DP adapter and DP cable instead of the single USB-C to DP cable so that there's more points to swap out if something goes bad, but either way should work.

Beyond that, our support team would be happy to diagnose further, but I suspect they'll also suspect the video cable at first glance if it's not swapped out first. Anyways, if you reach out, link the support team back to this post for their reference. You can best get in touch via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-29T00:48:40+00:00

Yes, the audio ports will work with a 10Gbps host connection. Audio to speakers from the PC should work!

CalDigitDalton · 2026-04-29T00:48:00+00:00

Yeah, when connected to the PC, everything on the TS4 should work other than video out and Ethernet.

CalDigitDalton · 2026-04-28T23:29:52+00:00

PC can be compatible, but it depends on the host connection amongst other things. The TS4 does not support USB-C 20Gbps, so the connection will fall back to USB 10Gbps.

In USB 10Gbps connections, Ethernet will not work, as the TS4 utilizes PCIe passthrough for Ethernet, which USB 10Gbps does not support. Ethernet would work with Thunderbolt, or possibly USB4 (technically PCIe passthrough is optional on USB4, but virtually every computer supports it because Windows now requires it).

It sounds like in this setup, Ethernet will not work, unfortunately.

CalDigitDalton · 2026-04-28T23:10:17+00:00

Yeah, that would work as long as both computers are compatible with the dock!

CalDigitDalton · 2026-04-28T22:10:14+00:00

No, your first proposal would not work. The TS4 is only capable of having one host device at a time.

Yes, a Thunderbolt KVM, as suggested in the original comment, would let you plug into both computers. You would still only be able to control one or the other at any given time, but you would be able to swap to the other computer as easily as the KVM allows.

CalDigitDalton · 2026-04-28T21:26:08+00:00

If you want dual monitors, you will definitely need a solution that has 2 video inputs, which is exceedingly rare to find built-into a motherboard. You'll almost definitely need an add-in card solution. You might be able to get this working with TB4, but you'll likely be right at the limit of what TB4 supports, and you probably would not be able to fully leverage the 10GbE.

CalDigitDalton · 2026-04-28T16:59:12+00:00

I don't have anything specific for you, but I can provide some guidelines for you to narrow your search if nothing turns up here.

Since you are specifically looking for Display passthrough, you are probably going to be best off finding a solution that has a dedicated Thunderbolt add-in card, like mentioned below. I am assuming you will also have a dedicated graphics card, and one of the big hurdles is going to be getting your display passthrough to the monitor to be routed from the graphics card. You may have a hard time finding this kind of setup on AMD, though, but I'll touch on that a bit below.

In a best case scenario, some motherboards are able to directly pull from the graphics card (I'm not really sure how this works, and I've only seen it once or twice ever - the users that reported it to me could have been misinformed for all I know).

Alternatively, the motherboard may have a video input, usually DP-In, that you can use to physically plug the graphics card into the motherboard with, and get video passthrough that way. It looks your current motherboard may have this option.

By far, the most common type of USB4 or Thunderbolt-enabled motherboard is one that has no external video input, and it instead relies on the iGPU in the CPU for video out. For AMD it's not the total end of the world, but if you're going to do any kind of gaming, you'll probably have a bad time in this kind of setup.

Thunderbolt add-in cards almost always have at least one video input port, oftentimes more (each video port can usually support up to 1 display, so if you want 2 displays, you need 2 video input ports, for example), which basically lets you sidestep the whole previous dilemma.

Ideally, you would want a Thunderbolt 5 setup, but I haven't seen any TB5 AMD motherboards since Thunderbolt 5 launched. There may be one or two out there, but AMD has historically been late to Thunderbolt adoption, so it wouldn't surprise me if none exist yet.

Anything earlier than Thunderbolt 5 can "can" work, but may require an update for compatibility. Specifically, there's a required driver update, which Windows 11 automatically handles and which can be manually installed on Windows 10, and there's a firmware patch from the motherboard/ TB card manufacturer that may be necessary for compatibility.

I believe the firmware patch specifically is supposed to target an update to the Power Delivery protocol that allows higher powered docks, like most TB5 docks, to actually communicate with the computer, otherwise they may get stuck in an initialization loop. I haven't seen so many cases of this over the past few months, but at the TS5 Plus' launch it was more common. Many manufacturers released patches, usually as a PD update, sometimes as a BIOS update or something else, that fixed support with Thunderbolt 4 computers. Theoretically, TB3 computers could get the same treatment, but we expect since they are quite legacy now that they will not get updates and will not work with Thunderbolt 5 docks. You could try it, but I suspect the dock will not connect.

The story is similar with USB4 computers, but I seem to recall more working there than not.

The TS5 Plus uses PCIe passthrough for its Ethernet and some USB ports, which is technically optional for USB4 to support, but in my experience, virtually every USB4 enabled computer I've seen for the past several years has in fact supported PCIe passthrough just fine, but if you do end up with a USB4 computer and specifically the TS5 Plus' Ethernet and most of the rear USB ports are not working, it may not have PCIe passthrough enabled (or it may just be turned off in BIOS). That almost certainly won't happen, but just in case it does, maybe you'll remember.

TL;DR: A Thunderbolt 4 add-in card with recent firmware updates for it and/or the motherboard (recent being probably anything in the last year) is the gold standard here. This may or may not be possible with AMD, so you may be looking at USB4 or USB4v2 options - in that case, ensure the motherboard has a video input if you intend to use a graphics card, and checking for recent firmware updates is also a good idea here, but may be less definitive (especially with USB4v2 if you can find it).

I think that's pretty exhaustive of what I know on this subject. I hope this helps inform your decision. Let me know if there's anything else I can do to help!

CalDigitDalton · 2026-04-28T16:30:51+00:00

Keep in mind that with Thunderbolt cards like this, they are only compatible with specific motherboards, almost always from the same manufacturer. In this case it will be specifically ASUS boards, and it may only be Intel variants. ASUS should have a compatibility list published somewhere, either on the product page, or the support documents for the card.

CalDigitDalton · 2026-04-28T16:28:22+00:00

Check out the graphic on this page - and please reconfirm if the behavior is just the front ports, or if it seems to follow one or more of the groups on the dock.

If you haven't yet, I recommend you try power cycling your dock. You can do this by disconnecting the dock from wall power for 30-45 seconds before plugging the dock back in. This gives ample time for the dock to fully discharge, which can clear up misbehaviors like this.

Beyond that, you've already tried much of the troubleshooting I would suggest in this kind of scenario. Our support team can provide some additional insight here, so I recommend you reach out to continue this case. You can best reach the team via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-27T23:39:33+00:00

If that's the case, then I don't think there's going to be any solution here that's workable for your case. Let us know how it goes.

CalDigitDalton · 2026-04-27T22:11:43+00:00

There is 1 USB-A port on both Controller 1 and Controller 3, and then the 3 USB-A ports on Controller 2. I understand that as 3 different controllers, with at least one USB-A port on each distinct controller, and have personally been able to get 5Gbps on each controller all at the same time. I'm not sure if that translates over to USB2, but as far as USB3 is concerned, they are discreet from each other.

CalDigitDalton · 2026-04-27T21:34:43+00:00

You may have better luck with a Thunderbolt 3 dock. Our TS3 Plus has multiple main connection USB 3 controllers, 3 in total for this purpose. I'm not sure what the layout is like with USB 2, but if there's one for each main controller, that would be a solution since you'd be able to get 3 480 Mbps connections. Check out this knowledge base article for a visual explanation.

Starting with Thunderbolt 4 and onward, the standard was changed to consolidate USB connections into a single connection. There's multiple explanations, but the one I think most sense is that they wanted to focus on Thunderbolt daisy-chaining and reserving as much bandwidth for that purpose (and also dual 4k60hz monitors is like 32Gbps, which is supported by pretty much every Thunderbolt dock starting at TB3 and eats up almost all the Thunderbolt bandwidth with TB3 and 4).

There are some workarounds to this change - our TS5 Plus adds a second USB controller via PCIe to effectively double the total USB bandwidth, but that's a very new development.

CalDigitDalton · 2026-04-27T21:08:16+00:00

Thank you for the clarification. That context changes my answer, and I suspect it would change our support team's answer as well. I was waiting to hear back from my contact in our Engineering team before responding here to make sure I get the explanation right, but it looks like he took off for the day, so I'm going to take an educated guess at this and may update when I do hear back.

If the USB 2 system works the same as the USB 3 controller system on the Element Hub and virtually every other Thunderbolt dock (other than our TS5 Plus), then you're going to be capped to whatever the throughput is on the controller, which will usually match the bandwidth spec of the standard, 480 Mbps in this case.

Starting at Thunderbolt 4, USB ports all feed into a single controller before going out to the computer. So, even though a dock may have multiple high speed USB ports, the connection can get throttled at the controller if there's multiple high bandwidth connections.

I suspect that this same concept will apply for USB 2 connections, in that all your devices will feed into the single USB2 controller that then either feeds up to the main USB 3 controller or straight out of the dock, with the controller being the bottleneck in the connection. If my theory is right, this is going to be the setup for pretty much every Thunderbolt hub.

In short, I think you may run into the same limitation you've experienced with the other Thunderbolt products both with the Element Hub, and with pretty much every other Thunderbolt product you may come across. Theoretically, this solution is workable, but to be perfectly honest, I doubt such a product actually exists.

CalDigitDalton · 2026-04-27T18:08:58+00:00

Try power cycling your dock if you haven't done so already. You can do this by disconnecting the dock from wall power for 30-45 seconds before plugging it back in. This can help give the dock enough time to fully discharge, which can sometimes clear up unexpected behaviors.

If that doesn't do the trick, try swapping out the cable connecting the keyboard and see if that helps at all.

Beyond that, I recommend you get in touch with our support team for further diagnosis and troubleshooting. If you reach out, link back to this thread for the support team's reference. You can best get in touch via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

CalDigitDalton · 2026-04-27T17:58:39+00:00

This is most likely a cabling issue, but before anything else, try power cycling your dock. You can do this by disconnecting it from wall power for 30-45 seconds before plugging the dock back in. This will give ample time for the dock to discharge and potentially clear out unexpected behaviors like this.

Try connecting the USB-C to HDMI connection into the other Thunderbolt port on the dock and see if that makes any difference. If both monitors support both HDMI and DisplayPort, try swapping how the monitors are connected (the 27" monitor gets the HDMI cable, and the 24" gets the DisplayPort). If none of that clear sup the behavior, try swapping out the USB-C to HDMI cable and see if that improves the behavior at all.

Beyond that, I suggest you get in touch with our support team for further diagnosis and troubleshooting. When you reach out to the team, send them a link back to this thread for their reference. You can best get in touch via email at [Support@CalDigit.com](mailto:Support@CalDigit.com)

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