Long time listener, first time caller here.
Wanted to share my experience getting M0 to work with a recent model Samsung phone without a headphone jack.
I figured that due to its diminutive size M0 would make a great external DAC for a Samsung phone that I recently got that sadly no longer has a 3.5mm jack. As many have found before, simply plugging M0 in does not result in the phone recognizing it as a USB Audio device. Moreover, this will drain the battery as by default M0 will try to charge the phone.
I was finally able to come up with a solution to make it work, although it may not apply to every Android phone (My phone has Android 11 update installed).
You'll need a full version of UAPP. Your phone must also allow you to select the device that's in control when plugging an external device into your phone.
I'm assuming you have UAPP installed.
- Set M0 in USB DAC mode with a menu toggle.
- Connect M0 to your phone with a USB-C to USB-C cable.
- Phone will likely see it as a storage device.
- In the USB mode menu that becomes available in the app drawer, select "Connected device" radio button in the "USB controlled by" menu.
- UAPP will pop up notification "Open USB Audio Player PRO to handle null?". Answer OK.
- UAPP will open with "USB audio device initialized!" message at the bottom.
- M0 will now display the USB DAC bitrate screen (48Khz/24Bits by default).
You'll be able to play music through M0 using UAPP, but not the Android system sounds.
Also, when I compared playback with Samsung USB-C to 3.5mm adapter (using UAPP bit perfect mode) I found that Samsung adapter had a more detailed and nuanced sound.