Alan Ratcliffe wrote
BTW, if you are using an older CRT monitor on your computer, upgrade to an LCD or LED screen and 90% of your problems will vanish.
my HUGE noise problem on the single coils was the room lights dimmer switch.....
couldn't figure it out until one day i was sitting playing in the dark when the wife turned the light on = instant noise.
have now got a normal light switch and tossing the dimmer.