Amp issue

[dyazdani]

I'm having an odd problem with a car audio amp. I've got a 4/3/2 Alpine amp in my truck and for some reason the left channel doesn't want to always work. When I first start the vehicle, there is no sound out of the channel, to fix it, I turn the volume way up for a second and then back down - it then starts working and stays working for a while. If it quits again I just repeat the volume thing.

Any ideas on what might be going on? When I first got the amp, it had a similar issue and I found a broken ground on the input circuitry (RCA connections). I checked again and didn't see any issues.

Thanks!

[dyazdani]

I was able to help it some today - filter switches seem to be a little dirty maybe. Switched the filter from "off" to "HP" and things cleared up. It's an old amp (circa '92) so I think I'll hit it with a few shots of Caig.