Sometimes I get a SNAP/POP when I turn on any of my DJ lighting and also when my Haze machine kicks on and off. I've changed out cables mixers and amps and I can not get rid of it, I have everything plugged into 2 Furman pl pro DM power conditioners, one for sound and one for lighting and plugged in to two separate outlets. Any ideas? I was told to add capacitors on the switches, All switches are 120 volts, but what capacitors should I use?