@geraldcarter2846 sorry I had overlooked this but it sounds like a bad connection. Bad mosfet would typically not work at all but there are some very rare instances where a bad mosfet could do what you described. Hard to explain but it's like the mosfet has shorted but not shorted enough to completely stop the operation. Seen it before. Based on what you asked though, it sounds like a bad connection. For instance after being on for a while a jack/terminal expands from heat causing a bad connection.
