Well, we had a brief flicker of the lights during a snow and ice storm.
Of course, it happened with my audio system on.
In my two-channel system, it took out a Panamax 4310, but left my Panamax 5100EX operational (I use two in my systems). In my home theater system downstairs, it took out my Adcom ACE 515 and another Panamax 4310! One event, three line conditioners!!!
I am assuming it was a surge, but our house is protected with a whole-house surge protector. Could it be an in-house surge caused by HVAC or dryer or other appliances? Is it worth it to fix these things?
Read the manual, for warranty information.
Why are you using two Panamax in one system? You should need one that can handle the loads. Use a non-suppressing power strip for the small loads.
Best practice-
Use whole-house protection or a panel-mounted device for the AV/network circuits and remotely located protection for surge sources in the house, like the ones you mentioned. Motors, relays and switches cause surges and spikes, too- these can be negative or positive.
Does your whole-house protection have status lights? How old is it?
Read its warranty/coverage info, too.
Also, have the power company check the connectors where their cables meet yours- I have seen houses where the anti-corrosion compound dried out and water entered, causing dimming when the Fridge or furnace kicked in.