Thump in Speakers When Wiper Switch Turned On/Off

I have a 75 caprice with a 3000 watt audio system. I have a easyguard ec002 push button start alarm. I get a loud thump noise through the speakers when I put on the wiper. The thump just happens when I move the switch on and off. When they are on I get no noise. I get a thump noise when I move the ac switch to power on. No noise while it on, just when I move the switch off and on. I checked my grounds. amps grounded to body, body ground to engine, engine ground to battery, battery grounded to frame and body. The noise seems to be only from the the switch itself. I gave power directly to the ac compressor and no noise, I gave power to the wipers and no noise. I tested both system unhooked from the switches. how can my switches cause a thumb in my sound system. No engine noise, that is the only noise?

Is your radio pull power from the factory harness? may try moving that and see if it helps

I tried running power from the radio to the battery sound sound was still there. I guess ill try to run hot and ground from radio to battery and see what happens