I need help, purchased my 08 g37 coupe with the radio not working. I get these popping sounds from the front speaker, I get sound but not until like 20 mins but for like 1 sec until it cuts off again with popping sounds. Went ahead and bought a radio head unit from the junk yard. Still does the same but at least the sound doesn’t go away for a second. Took it out and so I can return it. Maybe that headunit was also bad.(?) checked fuses and they were also good. Any suggestions? Bad amp? Maybe try another headunit?
(aux, cd, radio all with no sound)

 

Did you bench test the original radio prior to purchasing a replacement?
Check/test wiring harness pin connections

 

How do I go with the bench test? I’ve check the harness, cleaned it and everything was good. I also did the the self diag, nothing came up for the replacement HU, but when I installed the old one it gave me some codes, such as iPod connection, AV comm circuit 2, etc forgot the others.