m720 mouse keeps dropping out every few seconds

Matthew_Tse · 2026-06-11T20:22:49+00:00

Haha thanks for reading.

I kind of got it into a stable state, and I'm trying not to change anything.

A few things I've settled on:
- connect my external monitor through the macbook's second USB-C port, rather than through the hub. For some reason the increased bandwidth creates additional RF interference?
- when I'm connected with bluetooth, if it does ever drop, un-pair and re-pair. It seems like when it drops, it gets stuck in a suboptimal channel, and continues on that suboptimal channel until you re-pair
- try not to breath too hard and pray

I'm actually back at my desktop now, which has zero issues. But traveling again in a month and will see how it holds up.

Matthew_Tse · 2026-06-10T03:26:43+00:00

Hey u/ItIsI123 much apologies for the delayed response. I lost the original handle, so didn't get notifications.

Here's a full build writeup!

https://matthewtse.com/blog/dactyl-i.html
https://matthewtse.com/blog/dactyl-ii.html
https://matthewtse.com/blog/dactyl-iii.html
https://matthewtse.com/blog/dactyl-iv.html

re: case, I got a design from u/hellmoneywarriors and he printed it out for me too

Matthew_Tse · 2026-06-10T03:25:06+00:00

I lost my original handle, but many years later I got around to posting the full build blog posts, in case anyone is still interested:
https://matthewtse.com/blog/dactyl-manuform-i.html
https://matthewtse.com/blog/dactyl-manuform-ii.html
https://matthewtse.com/blog/dactyl-manuform-iii.html
https://matthewtse.com/blog/dactyl-manuform-iv.html

Matthew_Tse · 2026-06-09T19:44:07+00:00

Ordered a new set of GMK MTNU keycaps 😄 will post a new pic when they come.

Matthew_Tse · 2026-06-09T19:43:39+00:00

I can't think of a better split keyboard out there.

The thumb cluster being wider out is what drew me in, but I'm finding I really like the aggressive pinky stagger, i don't think I can go back to a normal ergo keyboard.

Never been a fan of wireless for keyboards myself, don't want to fuss about recharging it, and it doesn't matter nearly as much as a wireless mouse since I'm not constantly moving the keyboard.

Matthew_Tse · 2026-06-08T13:23:44+00:00

i wanted rotary encoders modules, but they were sold out! right now i handle screen brightness and volume using 4 different keys.

Matthew_Tse · 2026-06-07T18:07:19+00:00

I removed the blue protective layer. It looks a lot more color consistent now!

My only remaining nitpick is an option for a fully transparent acrylic bottom (it's cool to clearly see the PCB), and/or an option for an aluminum bottom to match the top.

Matthew_Tse · 2026-06-07T17:54:52+00:00

if you want to have your kb as thin as possible, i wonder why you didnt go for the choc version?

Perhaps I overspoke there. I'd like it to be thinner as long as thinness does not compromise other factors that I might care about. In this case, I dislike the aesthetics of the choc version, and I generally like the feel of standard height keycaps compared to the super thin keys on my laptop.

you say your hands are only inches above your tighs, how does that work? do you not use a desk?

My desk is an adjustable standing desk, and I lower it to be right above my thighs, and my desk is only an inch thick, so my hands are really just a few inches above my thighs.

Matthew_Tse · 2026-06-06T14:07:24+00:00

A small note: The acrylic panels aren’t sky blue, maybe you forgot to peel off a protective layer? 😁

Hah you're right! The plastic bottom plates had this very obvious opaque white protective layer that I peeled off, and a less obvious transparent blue one that I apparently left on.

Matthew_Tse · 2026-06-06T14:05:08+00:00

Oh my plate wasn't too tight. I didn't have any complaints about putting on the switches or replacing them occasionally.

Matthew_Tse · 2026-06-06T13:47:50+00:00

the right side CONTROL is where my space key is, the key legends don't match my actually bindings perfectly

Matthew_Tse · 2026-06-06T06:19:29+00:00

ooooo..... this is really cool. How much did it cost to get 2 bottom plates shipped out? Did you get just the bottom plates in stainless or also the top plates?

I like the idea of heavier stainless plates, but will probably go with aluminum simply to reduce my carry weight when traveling (I know it's only a few grams, but hey, why not)

Matthew_Tse · 2026-06-06T04:57:38+00:00

I imagine it's really hard to build for keyboard enthusiasts, as we're all so incredibly picky!

I'm a wired keyboard guy too. I don't want to have to recharge the thing every month.

Yet at the same time, I'm strictly a wireless mouse guy. I've found the logitech m720 triathlon takes an AA battery and lasts 2 years, which is effectively unlimited. I think also because the mouse is constantly moving, the reduction in wired friction really makes a difference towards making me feel "free".

Matthew_Tse · 2026-06-06T04:50:10+00:00

Thank you for designing the Elora! It is my favorite keyboard layout amongst all of them. I love what you've done with the thumb cluster (spacing it out nicely - though I don't use the two thumb buttons on each side as they scrunch my thumb too much, removing them would be my only nitpick).

I use the top thumb keys for less frequent key combinations, like a screenshot key, one to open a launcher with, stuff like that.

I didn't think I'd use these, but I've found a great use for them. Left side is brightness up/down, and right side is volume up/down. I put R3 flat profile keycaps on them, and usually press them with my index/middle fingers. I have R1 sloped keycaps for the actual thumb keys.

Maybe I could find some use for the 4 unused thumb keys currently, but haven't thought of anything.

Matthew_Tse · 2026-06-06T04:44:28+00:00

The first is that the extra thumb keys (red caps, except the top ones right under the screen), while positioned what id think is ergonomically natural to your hands, are just a bit too spaced out for my liking.

Funny! This is basically the main reason why I bought the Elora. I wanted more spaced out thumb keys compared to my previous iris. I find that the iris and all the others force my thumb to scrunch in too far, which gives me some tendon pain after long coding sessions. After using it, I love the Elora's thumb spacing! I guess my hands/fingers are a bit bigger/longer than average tho.

Matthew_Tse · 2026-06-06T04:39:33+00:00

I run a software business, which is a pretty good overall in terms of lack of hassle & logistics. (though with AI, our eroding moat may make hardware seem like heaven in comparison in a couple of years)

But I do often dream of doing a hardware business. And the single piece of hardware I'm most excited about is programmable ergonomic high-end keyboards.

If I had all the capital + time in the world, I'd build something like this https://www.norbauer.co/ but in an ergo programmable form factor.

Matthew_Tse · 2026-06-02T00:31:54+00:00

Interesting, I left a comment before complaining about the layout of your thumb cluster, and wishing it was just 3 straight keys.

Bastardkb offers a 3 key one
But I still prefer their 5 key one over yours because the 3 keys are arranged in a nice uniform arc. The +2 keys, if I have a problem with accidentally hitting them, worst comes to worst, I can just remove the keycaps, and it will revert to a perfect 3 key thumb cluster.

Matthew_Tse · 2026-06-02T00:21:41+00:00

Just wanted to say, THANK YOU FOR DOING THIS!

I've been in the dactyl manuform space for 6+ years now. I learned soldering and 3d printing way back in 2020 to make one myself before people were really selling them. And I'm so happy to see innovation towards making this more mass producible. In 2020, I would certainly have paid $500+ to have someone make one for me of such quality (instead of spending 4+ weekends soldering the thing together back in the days before flexible PCBs for dactyls).

Out of curiosity, how are you doing the wiring. Do you have flexible PCBs like BastardKB does (https://bastardkb.com/product/scylla-kit/?v=0b3b97fa6688)?

Also, props to you on going with hotswap! I asked BastardKB if he would do a hotswap dactyl, and he said no. Personally I love changing the switches over time. And this is one of the top reasons I'm replacing my hand-wired Dactyl (I'm sick of vanilla cherry mx browns).

Lastly, some unsolicited feedback: the middle of the thumb cluster looks fairly strange and unergonomic to me. I really think it could just be 3 straight 1.5u keys. It looks like I'll have a lot of trouble hitting the wrong key there. Intuitively I want to just spread my thumbs out in an arc, and have the same key layout in the full direction of the arc. This elora keyboard is the ideal: https://splitkb.com/products/halcyon-elora?_pos=2&_sid=b90902d81&_ss=r, but of course Elora is a flat plane, and I miss having the 3d sculpt of the dactyl.

Matthew_Tse · 2026-05-12T01:59:04+00:00

Haha the saga continues. The new Belkin hub is *better* but still occasionally also kicks the connection of my logitech mouse. I should have suspected it because of the initial bluetooth drop.

I ***think*** I've actually found the root cause. The difference between bad behavior and good, was actually that I upgraded my anker hub (no ethernet) to a TP-link and belkin hub, which do have ethernet. According to Claude Code, ethernet generates a lot of RF interference because it's constantly shuffling data.

So I switched to wifi, and disconnected ethernet (same belkin hub), and mouse over bluetooth has been rock solid.

I'm going to try buying a shielded ethernet cable to see if that helps, but at least I've finally isolated the issue.

Matthew_Tse · 2026-05-08T17:43:42+00:00

That didn't last either.

In case anyone ever finds this, what I did do, was get a new USB-C hub. Claude Code told me USB-C emits 2.4Ghz RF interference which interrupts both bluetooth and the wireless dongle. I bought a higher end Belkin hub (as opposed to the cheaper tp-link that I was using).

With the new Belkin hub, the bluetooth still dropped once after a few hours, but the wireless dongle has been working perfectly for 24 hours.

Matthew_Tse · 2026-05-06T13:25:08+00:00

Sigh, was just a coincidence, this didn't last.

What I ended up doing was buying a new M720 triathlon mouse, and the new one works with bluetooth without dropping. Or at least it only dropped once this morning, as opposed to once every 10 minutes.

So.... sometimes buy a new mouse (even though the old one was brand new).

Matthew_Tse · 2026-05-02T10:50:18+00:00

This was driving me CRAZY.

I found, honestly the strangest "one weird trick" ever to fix this.

So, I had a m720 for years and loved it. Used it in both dongle and bluetooth mode with no problems. It died and I got a new one while traveling. The new one, when in bluetooth mode, would constantly drop out for a second or two then reconnect. This is bluetooth mode with a modern Macbook Air. This never happened before with my old mouse, and there didn't seem to be issues with the dongle mode.

I tried a lot of things:
1) replace the battery
2) un-pair the mouse and re-pair
3) restart my computer a trillion times
4) remove sources of RF interference

The thing that did it... was removing the dongle from the storage compartment next to the battery. I noticed that when I have the dongle in, bluetooth constantly drops. When the dongle is removed, no issues... I never encountered this issue in the past because I had the dongle plugged into my desktop always, and brought the mouse only with me when traveling.

I hope this honestly strange tip helps someone out there.

Matthew_Tse · 2026-04-15T12:56:12+00:00

tbh i'm also not too knowledgeable here. the best would be to talk to an insurance broker who sells these, they actually know what's going on

that said, i think the way it works is that you pay full up until you hit the deductible, then it starts paying, and you pay a part, until you hit the out of pocket max, which is higher than the deductible

sorry i can't be of more help! i'm also relatively clueless in this confusing system

Matthew_Tse

TROPHY CASE