GenVibe - Community for Pontiac Vibe Enthusiasts

I'm powering 2 10" Coustic 4 ohm SVC subs with a MTX 311d mono amplifier. I've had this setup for nearly a year and a half. It's been working great. No problems, no complaints until recently. Now when I turn on my system, the bass is not as strong as it used to be. But after a few minutes the bass will boost as if I hit a switch, stay like that for a few seconds (sometimes minutes), then ease up again. The amp is not overheating. My battery and alternator are not defective. I've checked the ground and it appears solid. The setup was professionally installed, so I know it wasn't something I did. Any suggestions on what it might be? Amp going bad? I know the subs aren't blown, because I tried a set of brand new subs and I still get the same results. Help me out...Thanks,Kenny

Stock radio?How is the amp hooked up, RCAs?Could be the radio, the connection between radio and amplifier, or amplifier itself. Most likely not power if the sound goes quiet and louder, instead of on and off.

It's hooked up to an aftermarket pioneer through RCAs. The radio is about 5-6 yrs old. I checked the connection between the radio and the amp and everything is ok. Kenny