My one speaker pops when I change the "surround mode" or channel.?

Question

I have a Harmon Kardon AVR 247 audio/video receiver, and a polk audio 5.1 speakers. My problem is when I change "surround mode" or I change the channel with my Bell HD PVR receiver. There is a pop in my rear left speaker. When I changed speakers, it still is coming from my rear left. When I switched rear left and right speaker wires, the pop came from the left.

This means thats the pop is coming from or being caused by the Harmon Kardon receiver or the Bell HD PVR. Any help will be appreciated.

Answer 1

from your reciever