It seems to me that your problem is from one of two sources: the refrigerator or the power company. The refigerator motor contacts, brushes or pull-in relay could be arcing, leading to induction or impules noise in the entire house wiring. These voltage spikes can easily fry a CD player's electronics and blow amplifier fuses. Pull the plug on the refigerator and see if the problem goes away with respect to the light switch pops.
Second, the power company has voltage transients carried through to your house from sources such as nearby building motors or on-site generators, transmission wire faults, or your neighbors could be polluting upstream with their motors, computers, etc. This is a bitch to track down. The only thing you can do is complain to neighbors but the utility has a responsibility to attempt a solution if the problem is on their end.
Without knowing anything else, voltage spikes are the most likely culprits for the equipment damage. EM/RFI pollution is the most probable cause of the popping. If it were my house, I would be looking to install an isolation transformer for the entire audio circuit and a TVSS in the main panel.
