Hey first time post here, any help in troubleshooting would be appreciated, bought a car that has a system in it, everything worked great. I have 2 speakers in the front with tweeters and a sub in the back, there are no back speakers. Everything worked great until recently my left door speaker cut out. I took the panel off, checked the wires and one was loose, i tightened it back up and put everything back together. I noticed my left right balance doesn't work, it will go one way but not the other, if I flip the RCA's it has the opposite effect. I figured maybe it was a loose cable at the head unit so I took it off and checked. That did not seem to fix the problem. To be safe because I was in there anyways I had 4 RCA's 2 of which were not in use so I switched them to the other 2 and same as on the amp. When balance is center it does play equally through both speakers, but when I try l/r balance I run into the same problem one side goes deaf and the other plays. The odd thing is it plays both speakers through one RCA. I think it may be the amp but you would think it would cut out both speakers if it was an amp problem? Any help would be appreciated thank you