Never had a problem. Since what you are describing appears to be electrical in nature, you may want to buffer the incoming power source. A wildly fluctuating power source will kill off electronics in a seemingly haphazard manner.
You could try an inline uninterruptable power supply (i.e., one what doesn't rely on a "switch" but always sends power through the buffer of the battery) or get a cheaper solution with something like an MJF line filter (
http://www.hamradio.com/detail.cfm?pid=H0-008777), which is what I use. I have very stable power with less than 3% voltage fluctuation on average, but if you have more, I'd suggest the inline route.
Also check to make sure that you do not have too many devices on the circuit. Overloading a circuit will also cause power fluctuation. I have my two aristocrats on a 15amp circuit of their own.
One final electrical thought: you may want to check the ground to ensure that: a) there is a good connection between the ground (probably a rod) and the house power panel (no corrosion, etc.); and b) that all the power outlets on that one circuit have their grounds properly affixed. When we had this house built, we found several grounds wires that were not properly connected.
Good luck. Fortunately, Bob is the king of great customer service.