Is my question even valid? Like does quality get affected depending on USB vs Bluetooth Audio, etc?
As for me, I'll tend to listen to bass-heavy music (hip-hop, rap, dubstep, drum n bass, etc) and I find bass +6 is "good" but +8~10 would be the bestBut when I turn the volume knob to 15 or higher, the music quality tends to get distorted...probably because my treble is +5?
I could be wrong, and our music styles differ greatly, but I think I read some folks saying the fake engine sounds piped through the stereo will cause distortion when set to the higher settings. Did you try turning that to off?