Guitar processor noise...? BZZZZZZ!

My friend had this problem in his bass amp, seems the 6 string guitar amps didn't, I ran a ground wire to his face plat to the wall outlet, then to his amp housing, cleaned it up.
He had fluorescent tubes on his wiring to his power supply that was the main reason.
But I am sure all these musicians here have you took care of, a floating ground is almost a necessity like southwest bell used, as well as some or rooms.

Good luck and keep on Jamin.