You could be getting spikes in that circuit. Granted, it would have to be pretty major.

Plug in a lamp in the same socket all by itself. Turn it on. Does it flicker?

Technically you really need a meter to check for spikes but this might work too.



2xAA
M80/VP150/VP160/QS8
4xM3/M22OW/M2OW/VP150OW/4xM3IC/4xM3OW
EP500/800/HSU VTF3/SVS PB2k/SB2k/SB-12