There is a issue with the quality of sound from the Spotify app on all my devices, the bass is flat and the treble is dull even at 320kbit/s with no EQ or settings applied other than 'extreme quality'. I even tried deleting the app and redownloading then changing the quality again, which didn't help the quality. I've found that the web player is much better quality even thought it's 120kbit/s compared to the apps 320kbit/s, therefore the app is the issue in some way.
My equipment quality isn't an issue either.
Does anyone have any advice?