JadeAudio/FiiO JM21 Android 13 Hi-Res Music Player MP3 with Snapdragon 680, Bluetooth WiFi USB DAC 12.5H Playtime (Sky Blue)

I fell in love with it after only a few hours. This is my fourth Fiio player and I mostly knew what to expect when I purchased it. For the most part I am very satisfied with the JM21. My disappointment is with documentation and support from Fiio (more on that at the end of the review).The size and weight of the JM21 feels comfortable. It feels solid like my other Fiio players (X1, X3, and X5). Those players have held up to heavy usage and survived getting dropped too many times and all of them are still functional. I can't in all honestly say that the JM21 is easy to get used to and easy to use because I have used a Fiio Android based player before and find very few differences with the old interface. That said, I didn't have trouble adjusting to the old interface so I don't see most people who are used to android devices having much trouble. I have never used the iOS so I can't advise on the difficulty for those who are not used to Android devices.I like that it came with at least a silicone case and a pre-installed screen protector. I ordered a second protector but passed on a better case. I had the leather case for my X5 but found that it made access to the edges of the screen difficult without a stylus.The technical details of the audio processing capabilities are a bit much for a review but I can tell a definite difference in audio quality when comparing the JM21 to that quality of music on my phone or on the no-name player I have been using. I have tested it with JBL 770 Live headphones connected with Bluetooth and with Status CB-1 headphones connected with a cable. An added bonus is that as unlike when listening on a phone I don't have to worry about the music cutting out if a text or call comes in.I have mostly been satisfied with the battery life. I recently listened to an 8 1/2 hour audiobook on the Audible app and maybe an hour of music using the Fiio app (without using a headphone amp). I used wired headphones for the music and the Bluetooth connection for the audiobook. Wi-Fi was only turned on long enough to download the book. At the time I started listening the battery had a 100% charge. After about 9 1/2 hours of use and sitting idle overnight there was still 34% battery power left. For some reason the player dropped to 9% over the next 11 hours while it was sitting idle. Hopefully turning on battery saver and using the "Enter Sleep" app that is pre-installed will help with that. I do not have the feature that turns the player off after a certain time enabled but will do so if necessary.The JM21 has Android 13 (customized) installed and uses the Google Play Store as well as Fiio's app store. This opens up options to use most any software you want. I use my player for listening to audiobooks and podcasts in addition to using it for music and have been able to install my favorite podcast app, a player for local audiobook files. The Audible app was preinstalled.The JM21 does have a micro SD port for expandable memory (up to 2TB). Even if I wasn't concerned with audio quality finding a modern phone or with enough storage to keep my music on it isn't possible. I have more than 400GB of music in FLAC format and over 100GB of music purchased from services that don't offer lossless files. iPhones and the newer Galaxy phones don't have the capability to expand storage with a memory card. I listen to a lot of music digitized from old albums or from independent artists that are not available on any streaming service so the extra storage is a must. Even if all of it was available streaming there is always going to be a time when Wi-Fi isn't available. I have heard the argument that I don't need carry all of that with me but if I get the urge to hear a song I don't want to have to wait to be able to move it from my computer to be able to listen to it so the storage is a must for me.I gave the player a 5 star rating only because 4 1/2 wasn't possible and I feel it is too good for a 4 star rating. My reason for wanting to give it 4.5 is not because of dissatisfaction with either hardware or software but for lack of support from Fiio. There is no manual available for the JM21 at this time. Yes, it ships with a quick start guide and there is a FAQ on Fiio's web site but they don't list all of the features. I needed to find a way to lock some of the side buttons when the screen is off. I have not been able to find how to do that in any available documentation. I finally stumbled across how to do it when looking for something else in the settings. As soon as I got the JM21 I sent a request to Fiio asking for an actual manual and got a reply that gave links to the quick start guide, the FAQ, firmware download, two different trouble solutions, and an apology for being slow because of a higher than normal volume of help requests. This also happened when I contacted support for a problem with my X5 player about six years ago so if you purchase this be aware that you will need to rely on third party information for anything that is not in the in the FAQ or quick start guide. The quality of the player itself, however, makes the lack of direct support and information from Fiio worth the trouble.If you are looking for an affordable portable player with sound that is equal to that of the high end, expensive players and better than you'll get from any phone give the JM21 a try. It's not perfect but I doubt you will be disappointed.

Great HiFi player with a few caveats. After two weeks of fairly extensive use I am pretty familiar with the good and not so good. On the good side, fidelity on LDAC files is amazing even through normal AAC bluetooth connections. It seems to do a better end-to-end job than my Galaxy 23 or PC in getting music out with really low distortion (particularly found in high dynamic string sections). I use Media Monkey to manage a library of about 35K tracks and I was able to load and use my full 90 Gb library on a 128 Gb microSD without issue. Unbalanced output capable of fairly high levels. Did not check balanced outputs yet.I like the organization keeping audio controls on one side and power/device controls on the other. Very clean and easy to use.Screen is super clear and I find even small print quite legible.Battery life is excellent - easily making the 12 hours quoted.On the not so good - the APTX bluetooth connection does not seem to work with the one set of earbuds that have that capability; it does connect but when starting music it abruptly terminates the connection, so for any reasonable operation I have to use AAC. As to whether this is due to the Bose earbuds or this unit is impossible to determine at this point; both are Snapdragon certified so it is hard to understand.Also there are times (usually on first start up) that it will only play the first 8 seconds of the track then go quiet (while player continues to play). Skipping to next track gives the same behavior. If I then go back a track the playback usually becomes normal. Another odd stack behavior can occur with a pulsed dropout or with 2X or 4X normal speed playback. I don't yet know what the exact sequence is that causes this but they can be cleared by stopping the track and restarting. Thankfully this is a rare occurrance.Unfortunately the basic Android 13 functionality seems to not work as expected. Setting the sleep or power down to 10 minutes doesn't work when I set the sleep timer for the music. Once the music stops my Galaxy phone will go to sleep but this unit will not - it is still very much on when I get up in the morning. I have some other trials that may sidestep this issue,Overall a 4+ unit with excellent fidelity and some minor software bugs which hopefully will be corrected in future releases of the brand new unit.UPDATE: After buying a new APTx dongle for my stereo I find that the player automatically connects correctly, which indicates the problem is with my Bose earbuds not the player! Given that correction I increase my rating back to 5 star!!

I had to return the JM21 as it overheats using the balanced output into RCA jacks and controlling Spotify playlists through WIFI. This is not the way most people would use it so still rating 4-stars. Sound quality is fabulous using the Balanced output through a patch cable to RCA amp inputs. The sound quality is better than my older DAC and better than running computer through HDMI. I think if you are powering headphones, particularly high end ones with balanced input JM21 is going to be fantastic. JM21 works seamlessly with Spotify on High Quality Downloads and with lossless local files. The Android system is easy to use. Everything is great except for heat build up. Heat buildup is not a problem running modist DAC volume, but sound balance was best with DAC volume higher and sound system volume low. Overheating shut it down both on my home system and at a venue where I needed it. Battery life is 4-8 hours, easy 8 hours if just running headphones. I did not try JM21 using Bluetooth. DAC products with balanced output and Android (needed for Spotify) are few in this price range so I recommend giving it a try.