Mine sounds just fine via the 3.5mm jack... However, I've never tried the included headphones (they may be crap?), I've only tried it with some decent quality headphones that I use with all my audio devices... Sounds no different to my old Samsung galaxy or other MP3 players.
Bluetooth on the other hand is completely useless for media audio... It seems to sound fine on phone calls, but for music is very distorted for some reason
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