Stereo in boat

[Goatro]

So I could not get the stereo in my boat to work. It has power and comes on but no sound out of speakers. I was trouble shooting some wires with a test light and bumped the speaker terminal with the tip. All of a sudden its playing music. When I cut the power off same thing power no sound. Touched speaker with test light and magic. What gives evertime I try to play the radio I have to ground out the speaker. Yes the radio is grounded and the wires are not touching. Help!!!!!