I recently used my 7100 to bi-amp B&W 704 and center channel. About 10 seconds after shutting down, the tweeters emit a decaying low volume whine that lasts a couple of seconds.

Additionally, there is a soft chirp when the amp is powered up.

Any idea what can be done to eliminate it?

Thanks,
Greg

The pre-amp out use 3' outlaw cables to Y connector into amp ports. Think the y cable is shielded end to end.

The whine does not start at exactly same time. Two are very close the third is fraction of second off the two

Back Surround channels - Right Front
Surround channels - Center
Left Front and Center - Left Front