Ok I'll check out the speaker wires and see if anything is going on there. Then I'll see about taking it out of the truck and powering it up to see if it does it then. If so I guess I'll trash it and get something else.

Fmc400 I knew it didn't have anything to do with the 73-79 trucks I just didn't know if a modern radio had to be insulated cause of the metal dash in these trucks. I've never done a radio install in a vehicle this old.