I have an mtx 1501d amp. that was hooked up to 2 kicker L7 15s and when i turn on my radio and turn the volume up in any way my subs start making a weird and really loud noise almost like an amplified line noise it use to work fine till i blew a tranistor i had all three in the set replaced and turned it on and it was working fine till it started to make this noise i hooked up another amp and they work fine all the subs are at the perfect ohms and wired right but the amp seems to have a prob. Any suggestions??
I had the same problem. Its your rca inputs. They need to be resoldered.
Also check to make sure that your RCA interconnects are good. If you are using interconnects that have a screw on top piece, make sure that they are all tight. This can induce all kinds of noise.
Check for broken rca input GND.
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