So I recently kiked out and bought a chink bone conducting bluetooth headset. Unsurprisingly they kinda suck and it feels like someone is banging a drum on my cheekbones. However for some reason not advertised on the packaging it has a micro SD slot so I got excited, filled an old micro SD card I had lying around with MP3s and meekly anticipated freedom from the laggy/stuttering bluetooth menace. It didn't fucking work.

EXCEPT for 1 MP3 file I created in the 2010s and even then it only plays for about 3 seconds and then loops infinitely. I tried removing the ID3 tag, it failed to play. It's using ID3v2.3 UTF-16 tag so I tried upgrading it to a ID3v2.4 UTF-8 one and downgrading it to a ID3v2.3 ISO as well but both caused the MP3 to completely fail to play.

So I guess the firmware is chinked beyond hope but could there be a way to get this cocksucker to play MP3s? What could this broken firmware be looking for?