I just googled "dirty electricity"... OMG
I immediately bolted to the kitchen and wrapped myself in 30 m of tin foil and made myself a boat-shaped hat out of it for good measure... My oh my what a can of worms...
One thing I did learn and which doesn't look like a ton of horsesh#t is that switching power supplies cause a good deal of electromagnetic noise. I have a cheap laptop power brick that I used initially for my DIY buttkicker and it caused MD to go totally berserk (no UPS), even when plugged into different wall sockets. So, leaving aside the issue of whether your dimmer switches or PC power supply are giving you asthma or diabetes, it's worth taking into account that these things might also affect the module.
If it ain't broken... fix it until it is.