Those of you who have heard interference with phones: can you confirm it is gone with 3G / LTE?
Enyone can still experience it with 3G / LTE?
I found it worse with 2g etc but there is definitely interference with 3g/LTE, it is like a crackling sound in the background that you can just about hear during quiet bits in song.
Sorry no I don't think you can turn it off, I think any app that doesn't use it's own USB audio output protocol like UAPP, Onkyo HF or Hiby gets up-sampled automatically by the stock android USB audio out.
If you are running stock CyanOS like me make sure AudioFX is turned off also, this can effect the sound output.
I'll do some digging around to see if I can find a better explanation for you.
Yeah I disabled AudioFX straight away because it was causing a funny glitch at the beginning of the first song played in Spotify. Regarding the up sampling I guess it isn't the end of the world if I can't turn it off so I will just live in ignorance!