Check your mains voltage coming into the building you may be suffering an overvoltage condition it should be anywhere from about 230v to 245 ish if it is higher (250-260) contact your electricity supplier. or place power conditioners in front of your valuable kit.
We had it in our old offices, it caused hums in power supplies and an increase in the rate our lightbulbs needed changing (3months typically)
Marie.
see attached PDF you might be able to claim compensation if anything prematurely dies
EDITED: 21 Aug 2014 13:57 by MIZZY