I have the base gsr radio and when its on 45 i can still barely hear it. When i go over a bump it will return to normal sound for a split second then go back to being super low.
My cd will also reset if i hit a bump hard enough but im guessing thats normal due to the ****ty cd player.

 

is the automatic volume control off ? also if you still have warranty take it in and get it replaced, i had mine replaced twice. once for low volume and once for cd stuck.

 

I don't know if automatic volume control is on or off. I don't know how to toggle that.
I have no warranty eather. I might aswell get a whole new cd player because the radio is louder then the cd.

 

Sounds like either the amp is bad or the head unit its self. Putting a aftermarket player will solve both.

 

Yeah, the base non-RF stereo is supposed to have auto volume control, but I've never come across a setting to turn it off.

Maybe it's just a glitch? You could probably try disconnecting the battery for a few minutes and see if the stereo resets itself.

Your 3-year bumper-to-bumper warranty has expired already?? Just saying, cuz if a dealer told you that you voided your warranty for putting on say a turbo-back exhaust or something.. they are still required to fix a faulty stereo under warranty, if it hasn't expired already. And even if you bought the car used, I think the warranty transfers to the next owner.