Hi, this is going to sound like a daft question but the manual doesn't answer it. I have the normal Hyundai stereo in my gen 3.5, and when i select the 'rock' setting, the screen says "bass---treble" but I can't see a way of actually adjusting the bass or treble - should I be able to or is it just a readout?? Doesn't come up for any of the other settings, e.g. 'pop', 'vocal' etc. Thanks!