Is My Amp Broken?

[BreathLess]

i bought a MRV F-545 alpine amp today, i got my sub and splits running of the amp, the problem is when i turn the volume down the speakers turn down but the sub stays at the same volume, even when on zero the sub still hammers away.

[RANDY]

How's it hooked up?

Like.. is it a 4-channel amp, and your head unit has 4 RCA outputs on it? So you run the splits off the front channels of the amp, and then run the sub off the rear outputs, using a built-in crossover in the amp?

I can't see how this could happen, with the exception of maybe the sub channels on the amp have the gain all the way up, so when the splits have nothing, the amp is amplifying the tiny bit of noise that is still coming out of the headunit?

[BreathLess]

I found the problem one of the RCA connections was broken for sub control so it couldnt be turned up or down. just changed the connection and its all fine. should have though of that last night. its so much easier to think when your not in a rush.