I found a few Videos on youtube.com, check there.

 

Take the screw off the little trash bag holder on the passenger side then the whole center dash piece pulls off. Then you can use a screwdriver to remove the radio bracket and wont have to mess with the radio itself. The infinity system only plays bass on the front doors and highs on the dash. Thats may be why you cant hear it. Personally I would go back to a stock radio. Its much easier and looks a lot better. Its pointless to have a million features you can adjust on a stereo. The infinity system sounds great. There isnt a reason to mess with it.