Sharp popping sound from panasonic shelf system.

[djg320]

Hey all,

I've been having a weird problem with my Panasonic SA-AK630 lately. It is a bi-amp system in the receiver, the main amp (which powers the main speakers through dual wiring into the enclosures, separate highs and mids) is having a problem with the right midrange channel. Every so often, I get a loud and sharp pop, almost a CRACK from the midrange. The fan seems to be working fine, so I don't expect that it is overheating. I re-stripped some fresh copper wiring from the amp to speakers, and it is still doing such, along with using a different source (plugging into laptop, then MP3 player) with the same problem. I use a standard phillips RCA cord for the aux in. It seems as though this problem is also there while using FM, so I don't expect that I burned out the RCA cord.

Any ideas as to what's up?