It is probably a really faint squeaking beep. If it new, then it is probably a ground. We are going to assume this to be a 2000 era boat or before. This was common, and could be moisture in the key switch also. You can try air drying the key switch, check all of the ground connections wherever you can find one. On the block, individual grounds screwed to any area. Check them all. You can spray air into the key switch and then put some lube in it. Is it possible you never noticed this before, and now the area you were in allowed you to hear it? The reason we say that is it is common in the 90s to have this issue on brand new rigs. Often they eventually discovered the buzz, when it was always there.Though now you have some things to look at either way. And while we can not be sure, this should not be or cause any damages. BCB
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