strange electrical problem

[Miss Charlotte]

Let me explain. Few weeks ago I tried to use my handheld vhf by plugging it into the 12v receptacle in the dash. No power coming thru, back at the dock I flip the main switch off and on now the 12v socket is working. Kinda of forget about it until today. I installed a new stereo other day. Wired into the fuse block with the other electronics. the radio goes on when the main and electronics switches are thrown working fine. Today the sound cuts out, radio still has power the lcd face is still on can use all the buttons just no sound. Not even any static from the speakers with the volume all the way up. Before we are leaving the fuel dock I throw the blower switch and the sound comes back. Does the main switch have contact points that might be dirty or something that could be effecting the other electrical circuits? I am stumped.

[Split Decision]

That main switch activates a solinoid which has contact points. It is possible that they are burnt and making just enough contact to operate low voltage draw. Maybe when you turned on the blower it made better contact to allow the stereo to work. I would say change the solinoid out. I think 27$ from CC.