Sat - the saga continues! Do you have a laptop you can use to run test tones through the M80s? If so, you might want to run a signal sweep through the system using a free program like REW to see where (at what frequencies) the M80s start to crackle.

This might help you pinpoint where the problem occurs, test different surround modes on the receiver, test speakers individually, etc.

Jason

Epic 80-800: HG Cherry