Well, I am wondering if anyone has ever experienced something like this:

I have an Alpha PMA640HCA 4 channel.

I have the front two channels running my Alpha 6.5" componants at 4ohms and the rear two channels bridged to one at 2ohms. It has ran great for a few months since installing it and even made the 16+ hour trip to and from the dragon with no issues. The amp has about 150 hours on the meter IIRC.

Recently, the left front channel has cut out to just a faint level only audible if you put your ear up to the speaker/tweeter. The right front channel plays loud enough to hear, but seems lower than normal. I cannot really tell if the sub channels have been reduced as they are still audible, but I tend to think they are playing reduced as well.

I began troubleshooting by reversing the RCA inputs to see if it was the signal, but I got the same result. I then checked all the connections at the crossovers to make sure they are solid, and they were. Finally, I was going to check the speaker conencts at the amp. When I removed the right front speaker wires, the left channel began playing normal again. I then put the right front speaker wires back in and everything played fine until today when the same cut out and reduced volume began again.

I am lost as to why this could be happening. Any ideas?

 

Check your speaker wires. One might be grounded out somewhere.

John

 

Think I have tracked it down to a bad RCA cable. I don't know how this can be because I checked them well before by switching them. Makes no sense to me, but oh well. Working for now with a replacement set of RCAs. Let's hope it stays fixed.