I use surge protected mains adapters with my PC equipment and my last mains adapter got thrown out because one of the on/off switches started sticking in the 'on' position... I've since bought a new one (different brand) and i'm now having the same problem! The on/off switch seems to stick in the 'on' position after i shutdown my PC and try to turn the mains power off through the adapter.
On both occasions the sticking switch is related to the adapter socket that the PC is plugged into. I find this strange and don't know what's causing it? Anyone have any ideas? A few nights ago i tried to switch my PC off using the mains switch on the adapter and it literally 'pinged' back into the 'on' position which created a small buzz... This caused the electrics in my house to trip.