Howdy all... Long post inbound!
Ok here's the problem. I'm running a Pionner Premier DEH-P860MP Head unit.
It feeds a 4 channel amp and a bridged 2 channel amp, both mid quality brands you don't get in the US. I've had them for some time, and have used them on my new set up as a go between till i get better amps.
Anyways, everything was working fine. Nice sound, no feedback etc etc... I've built plenty of simple systems.
So, i'm away 4WDing on the beach, and while everyone is packing up camp in the morning i'm sitting in the 4WD which is not running listening to the sounds. Then when we're leaving i start the truck and the stereo goes ballistic! The speakers were popping, like they were playing a beat, and it started screaming some massive electric sounds that pierced the eardrums almost.
I tried a few things to diagnose it. I ended up chasing it back to the sub amp, in which i thought it was a loose ground/earth wire. So i fixed that, and turned in on to hear the same sound. So i pulled the power from the sub amp and everything went back to normal (no sub, but with it going it effected all the speakers not just the sub)
So me figures something chewed out that amp, even though it has it's own fuse which was unnafected. But then about two days later i start the car, and now i've got ignition feedback through the speakers. You know, like the cheap system we first built, it whines with the revs, and turning on the head lights make it worse etc.
Now i'm wondernig if anyone has any suggestion to what has gone on? One minute all is good, no feedback, everything works, then i lose an amp (maybe), followed by an addition of signal interference. Surely it couldn't be the amps like that? And it can't be the signal, the HU puts out 6.5V and i've run the RCA's away from the old power cable myth..... Oh, and both problems have followed a physical starting of the 4WD.....
Any ideas? Any questions to further predict it?
I'm also wondering, in the meantime, if i run the HU directly to the battery instead of an ignition source; will that stop any ignition feedback?