I read on a topic that someone plugged in a dimmer switch and then plugged their sewing machine into the switch and you can control the needle speed while you are FMQ. Well last night I bought a dimmer switch and tried to use it but my machine kept faulting out. I have a Singer Q7469 electronic that I do my FMG on and I don't want to short it out. Anyone else have the same problem or any others? Maybe I shold try it on my Singer 401.