For the longest time I had some appreciation for the factory stereo. One of the few cars I've been in where the original unit actually sounded pretty good. I added in a sub to even out the lack of bass and it was great. Over the last year or so I've noticed the unit's output getting weaker. It can't even output enough of a signal to keep my amp active. My amp has a signal sensing power switch that I can't override. This means my amp just drops out all the time.

While I used to have my volume between 8 and 10 I have to crank it to 20 to achieve the same volume. The bass output is a bit lacking as well, when it's running. Lower mids are almost nonexistent so bass guitar isn't really there.

Anyone had this problem? I know one 08 fit owner who said they might be having the same problem. I'm wondering if it could be my battery since I did replace it over a year ago and maybe it's not putting out enough power. Anyone have suggestions for testing? Should I just replace? I've installed an aftermarket in every car I've owned but this one.

EDIT: Thought my sig had my model info. I'm driving the '07 Sport AT.