Yeah, that'd be easiest; just replace your door speakers with some good ones. Factory speakers are never good anyway, and door speakers ESPECIALLY get pretty much ruined over time. I'm guessing they have paper cones, and the moisture that gets inside of the door practically melts the paper coned factory speakers til there it sounds like crap. Get a decent set of 6.5s and it'll sound a lot better.

If you want a GREAT sounding stereo, replace the doors speakers, the rear shelf speakers (6X9s) and get a 4 channel amplifier. It wont be an annoying BOOM BOOM BOOM stereo but it'll sound great.

- Ca$h