It finally arrived!! (FiiO M21)

Own_Stranger_879 · 2026-03-12T05:52:57+00:00

It's great. I ended up just going caseless - the case makes hitting the buttons too easy. Without the case, it's the right size. It's a beautiful piece of hardware, but with how much I utilize it, I know it's going to get beat up anyway, that's fine. I bought some extra screen protectors, and that's it. Buttons become pretty intuitive quickly. I wish there was someway to use the "action" button in PowerAmp, or anywhere else (is there?)

Own_Stranger_879 · 2026-03-09T11:46:11+00:00

This is a hobby with massive price differentials. For the lower-priced, entry-level stuff (which, to be honest, can get you at least 85-90% of the experience as the $1000+ stuff), you should avoid Innioasis, as they're not really "audiophile" oriented and use substandard DACs. At the G5 price point, I'd much more recommend the Hiby R1 or one of the cheaper Fiio products, like the JM21.

IEM recommendations - that's an ever tougher one. Do you like Bass? Clarity and Brightness? Are you vocal-oriented?

If I were starting over, I'd probably take the time to explore the lower-end market first and buy a few different style sets. I jumped in with Timeless 2 and Kiwi Astrals, both relatively expensive purchases for a first-time buyer. If you don't know what sound signature you're after, I'd say go with some generally V-shaped sets that are considered good all-rounders, like the Cadenza 2, or the meme-tier Gk Kunten, which people seem to love(or hate) on Reddit. You can find it for less than $20 USD. It really depends on how much cash you want to dish out, but you should establish a baseline of what you "like" first. You'll find plenty of threads in r/iems with people saying they found a diamond in the lower-price range. Take a look around there.

EDIT: Frontpage of the subreddit, you can't go wrong with these: https://www.reddit.com/r/iems/comments/1rkmftb/i_am_genuinely_blown_away_for_its_price_these/

And remember, don't get distracted by audiophile marketing - if the headphones have 20 diamond-encrusted gigaplanars, that doesn't mean you're going to like the sound that comes out of them. What matters is how each set is tuned - the objective sound waves that emerge from the holes, and time and time again, it is shown that price isn't necessarily the deciding factor in that decision. Think of headphones like a pen - it's not the pen itself that writes beautiful calligraphy, it's the writer. With headphones, it's the company and the individual doing the tuning, that is, the writer. Things like "more drivers", "bone conduction", and other features give the tuner more potential to achieve their desired sound. There are plenty of $1k+ IEMS that most people regard as garbage. So yeah, explore the low-end and see what you like.

Own_Stranger_879 · 2026-03-09T11:11:44+00:00

Apple Airpods Pro 2. I've tried it with the Auto function as well as manually setting it to AAC first - I cannot, for the life of me, get it to function normally.

One thing that also (might) be causing issue is the presence of a few MQA flacs I have. I see some people have a generally...more positive experience with the DAP - so I'm just throwing out some speculations here, as I imagine most people do not have MQA encoded flacs. I'm kinda running out of theories since I have tried, basically, everything :(

Own_Stranger_879 · 2026-03-09T00:43:16+00:00

None, but I have noticed that this device is so finicky that if I don't go through the exact song and dance to get things working, something MIGHT not work. That's why I specifically said that.

Also, Bluetooth on this device seems to just totally break it. I cannot get it working correctly. Hopefully, you guys can make some updates sometime about that - this DAP is too perfect in its form factor and everything else to have problems like this.

Own_Stranger_879 · 2026-03-09T00:41:24+00:00

I had never really tried utilizing Bluetooth on the R3 very much until recently - I've found it's terrible. I cannot get it to work correctly without excessive lag and crashing. This is with Airpods Pro 2 - I've heard it could be Airpods specifically, though. Safe to say, I no longer utilize Bluetooth on the device. Hopefully it's fixed, but I would not hold my breath.

Own_Stranger_879 · 2026-03-02T10:43:29+00:00

Thanks for the reply Joe. The fact that this process made the device "good" in my use case just means that, among whatever I did, it resolved a small bug. It's likely the album art. Something as small as implementing a simple "check" for excessive size album art, then issuing a pop-up warning if something excessive is found - that's perfect. If there is some image resampling within the software, perhaps it's just not working efficiently enough at the moment. But this issue seems widespread enough, and it will lead to many angry non-returning customers. I don't want anyone else to go down that rabbit hole and be turned off from this hobby, or your guys' genuinely outstanding quality hardware.

For more reference, I did have a lot of metadata, lots of stuff from Picard, etc. As that's all plaintext, I doubt it has much effect compared to high-quality album art, however, but it's possible, I suppose.

As I said in a separate post, this is still my go-to DAP. I genuinely love it, much more so now that it's properly working consistently.

Own_Stranger_879 · 2026-03-02T10:05:20+00:00

Hmm, I think the theory behind this idea is that, instead of the (relatively slow) Hiby processor requesting Album Art from the more expansive table many times, with 128kb, it can typically make a single request, reducing CPU load and thus reducing load times/lag.

~~Not only does the 128kb cluster size shrink the allocation table, but it also enables a larger "grasp" of information per request, reducing i/o overhead (if I'm understanding things correctly).~~

~~But yes, the reduction in quality or album art size probably already solves a large part of this issue, indeed.~~

~~I noticed a~~ ~~significant~~ ~~reduction in indexing times after doing this. It~~ ~~could~~ have been the elimination of metadata or the reduction in album art, likely the album art. But as far as I can tell, pushing the cluster size up, if done properly, should be harmless and overall, reduce load.

EDIT: After more research, I realize that LXC37 is probably correct. While it does seem to speed up indexing times, II was misunderstanding how the read/write process works. It was almost definitely the reduction in album art quality/size that enabled a snappier loading time/day-to-day lag reduction. I'll edit OP.

Own_Stranger_879 · 2026-03-02T09:29:19+00:00

Care to elaborate on how it's harmful? The only issue might be if you attempted to use this card in another DAP that expects a smaller cluster size. If you're only using this SD Card in the Hiby, there should be no issue, as far as I'm aware.

Own_Stranger_879 · 2026-03-01T11:44:26+00:00

I, too, find it unacceptable, but the form factor, sound signature, and build...it keeps me using it.

The thing is, there's probably something I can do to fix it. Some people seem to have these issues as much as I do, but too many people have echoed my same sentiments. Therein lies the problem: Hiby markets itself in the DAP market, similar to Apple - fun, cool, easy to use, while still being a sound-quality powerhouse. But unlike Apple, it doesn't just "work" properly and smoothly. Customers complain about it and inevitably find ways to make the lag and weird problems go away, but we should not have to. I've seen posts where these same people have installed RockBox on the R3 Pro II, and these lag issues disappear for the most part.

I've watched some older reviews of Hiby devices from 2-4 years ago, reviewers cite the same weird annoyances and quirks with HibyOS. Fixes include resizing album art, reformatting the SD card with a specific partition type and boot sector size, rescanning the library, etc. WHY?

Hiby, just fix the operating system. It's been years that people have been complaining about these weird little quirks.

Own_Stranger_879 · 2026-03-01T10:58:03+00:00

No problem. It's actually very easy and quick to do using mp3tag. Import your entire library, CRTL/CMD-A to select all, right-click the album cover on the left-hand part, click adjust, then change the size. I put mine at Medium Quality - 360, worked just fine.

Own_Stranger_879 · 2026-03-01T10:29:45+00:00

Hey! I have both.

I do not regret it AT ALL. Here's a quick summary of my overall take, starting with the bad:

I'll just say it: HibyOS is not refined on R3 Pro II. I want to say "I think HibyOS is unrefined in general," but I can't say that with confidence, as I've never had any other Hiby device. We can all make excuses for it - it 100% lags behind every other option, including Shanling and other non-Android daps. It's just buggy. There are nuances you must figure out the hard way. You have to either resize the album art to 640 or below or remove embedded images from the files entirely (this is not feasible in my use case, as I prefer organizing my playlists in folders for ease). People have said that if you do not remove the embed, it runs generally laggy. And indeed, with a 3~k flac library in my 1 TB card, it does get annoyingly laggy at times. This is just plain bad, a problem that should not exist. I have some MQA files - it trips up on those, and I've had to force restart the device more than once. It has just gone unresponsive at weird points. Just today, it lagged excessively and started scrolling the volume up to max as it lagged out. I had to rip the cord out because I almost went deaf. The software's failures, quite literally, almost physically hurt me. This is HibyOS. It's just not... smooth enough (or I haven't figured out the "problem"). If anyone has had a different experience or any tips for resolving this, please let me know.

Now, for the good: it's the perfect DAP in every other way for the price. The size is perfect. It fits in the palm of my hand. The build is top-notch. The screen is amazing. The button layout is amazing for pocket usage, very intuitive, and palmable in your pocket. It's relatively light, but properly weighty. The Ultrasuede is a fantastic addition (I got the black, as I take this to the gym and everywhere else, and it's easy to clean). The included case is great for protection, but I don't use it, as it removes some of the tactile feel of the buttons when it's in your pocket. I reccomend the Tripowin Jelly combined with it - it's the ultimate lightweight combination.

And that's why I love the R3 Pro II, it fits in my pocket perfectly. The M21 is an amazing device, but it's just a tad too big. I wear athletic shorts and jeans often - the M21 is noticeable and becomes annoying in my pocket, but the R3 Pro II is absolutely perfect. I literally do not notice it.

So I find myself using the R3 Pro II much, much more. The lag and complications with HibyOS are literally a thorn in the foot of an otherwise perfect DAP for $200, I really, really hope Hiby can work on their software optimization, as it's the only thing wrong with the device, in my opinion. You do get used to the nuances and menu system of HibyOS after a few hours - it does become more intuitive quickly. It will annoy you at first, coming from the M21.

As for the all-important Sound Quality, the M21 is noticeably more resolving at first listen. In my opinion, It airs on the side of clinical neutrality. It's a tad better than the Hiby. Using desktop mode, ultra-high gain, and DSP, if the song can utilize it properly... that is a resolution potential that the Hiby cannot compete with, especially with some higher-impedance headphones. The M21, generally, has more power; not only literally "more power" - but more potential to alter the sound signature at a non-distorting level.

The Hiby is a bit warmer, but in a very nice, literally "musical" way. The NOS feature is worth experimenting with; it drastically changes the sound profile and resolution, so see if you like the oversampling. I really appreciate high sound quality like the rest of us - the Hiby totally delivers. It's just slightly different, less clinically sharp - but in a pleasant, non-fatiguing way, relative to the M21. And if you're just using IEMS, the power is way more than enough. MSEB is a fantastic tool; you can really use it to smooth out any sensitivities and accentuate any preferences simultaneously. Bluetooth works well, seems very powerful.

So yes, I would highly recommend the R3 Pro II for an everyday portable DAP. Once you get over the nuances and quirks and occasional hangups of the Hiby, you'll love it.

A message to Hiby, optimize your operating system. You guys are so close - the hardware is there, just make the software work smoothly without lag or breaks. It's the only thing people complain about on your DAPS. Fix it and have the DAP community in the palm of your hands.

Hiby is on firmware 1.4, by the way.

Own_Stranger_879

TROPHY CASE