We had a McIntosh MC2255 in for intermittent audio dropouts and noise. We isolated the issue to poor connections at the input connectors. The original connectors weren’t reliable, and one of the connectors was loose in the chassis which may have been causing grounding issues. We quickly replaced the connectors and the amplifier audio is as solid as new.
If you are having intermittent or noisy audio, or audio dropout, it may be your connectors. Contact Bob the Tech Audio for your service needs.
