The first word on Fiio’s web page for their new M3K dedicated audio player is “affordable.” Usually, citing low price as a flagship feature would be a bad sign — you might expect a cheap plastic device with lackluster specs and basic components. Luckily, this isn’t the case with the M3K. Though there are compromises in its design, the M3K mostly punches above its weight class, and above its “affordable” price tag.

Out of the box, the M3K looks and feels like a very modern update of the original iPod mini. It’s small and light by any standard, with a silver all-aluminum housing with rounded edges; it feels extremely comfortable and sturdy in the hand. A silicone case is included, but we prefer the M3K naked. Where the iPod mini had a modest monochromatic display and resistive clickwheel, the M3K has one large piece of glass (with screen protector pre-installed) that features a 240×320 IPS LCD display (non-touch) and capacitive touch control area.
The display is admittedly small (album art is displayed at about 1.75 inches), not terribly bright, and lacking the extreme viewing angles of modern smartphone displays, but is certainly adequate for this application. Physical power, track, and volume controls are located on the left side of the M3K — they’re clicky, but without a “Hold” button, they are sometimes accidentally pressed when the M3K is stored in a pocket. All the M3K’s ports are located on the bottom, including a 3.5mm headphone jack, a microSD slot, and a micro USB port. We would have liked to see USB-C like on Fiio’s BTR3, but at this price point we don’t expect the newest of everything. Our only real design critique is that the M3K would have been more pocketable with a wider, thinner form factor rather than the chubby 2004-esque rounded rectangle.
Unlike Fiio’s M7 and X7 that run Android, the M3K runs a customized Linux OS. Its interface is an improvement on that of Fiio’s X3 MkIII, greatly simplified to focused on music playback with just one extra feature — audio recording — for added flavor.
Navigation through folders is accomplished with simple up/down/left/right swipes and taps. Some notable features are absent here: the M3K has no Bluetooth, bass boost, gain control, hardware button lock, or lyric display.
What remains, however, is all the important stuff. The M3K’s 1Ghz processor is snappy and responsive (although album art can take a few seconds to load), and its AKM AK4376A DAC can decode just about any file format you can imagine, in resolution up to 32bit / 384kHz PCM or DSD64, and is Hi-Res Certified. Gapless playback is, thankfully, still present, and a basic 5-band equalizer is included with a few presets. The M3K can also function as a USB DAC, though playback is limited to 24bit/192kHz and there is no Line Out mode available. Its battery life is excellent; Fiio claims up to 26 hours of playback and 38 days of standby and we believe it, since we were able to go through the entirety of our testing over two weeks on a single charge.