its you're eq..... you can fine tune it with that option.... what i have allways done is...
turn all my reg audio options all the way down... everything ( high, mid, low, eq-ex turn all down...) then i would put in a cdi know by heart.. turn it up to 35% of full volume... and then i would go threw all the fine eq options and fine tune it till it sounded perfect... then go back in to your regular audio options and adjust them acordingly...