Erik, this is very important. Can you specify more. Where was the ground fault. How did you fix it. I am not too far from thinking that is the same cause in my case but I need more info. Did you add any filter circuits to it? Which part of your circuit was not properly grounded?
I will appreciate all the info I can get from you. I've had this noise problem for a while and cannot get rid of it.

Thanks!
J.C.