I installed a brand new system 3 weeks ago. It was playing very well for the first 2 weeks. I also purchased a brand new battery under the hood. Last week I noticed the bass was not hitting as hard. Then I get in the car again and it's working. The problem started happening after I removed the head unit and reinstalled. Last night I noticed when I mess with the subwoofer control on the hu up and down the bass will all of a sudden come back full power just to fade back to being quieter. The subs are the only thing doing this. The component set still plays just as loud. The subs still work but just aren't as loud as they should be. Like I said before the first two weeks everything was working great. I know my ground is not that good right now. It was a quick install and I haven't had much time to mess with it. I didn't scrape the paint off of where I grounded it. I do plan on doing that and doing big 3 this weekend. I was just wondering if this could be a ground issue or maybe my alternator is not capable of handling as much power I'm trying to push. Has this happened to anyone or anyone have any suggestions?