[Stewart Vernon]

I had a bad UPS/suppresor recently that actually could have caused more damage than it was supposed to protect! The way I found out that it had gone bad was when it started shutting down whenever my air conditioner would kick in... exactly the sort of thing it was supposed to be conditioning the line to prevent! And the only way to reset it was to power it down, unplug, then plug in... AND it no longer supported simultaneous turn-on of my TV and audio receiver as it had up to that point.

Luckily no damage to my equipment, and my new supressor is working like a charm.

So I second the recommendation to look into a new protector as your current one may be on its way to a breakdown.