Jim Thompson wrote:

Anyone make, or have suggestions for, an automatic audio switch...

Input with a signal gets connected to the Output ??

I've built something like that into a PA mixer for use in churches &
conference rooms about 10 years ago. If you look into that sort of
equipment, you'll probably find what you need.

--
Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
"If it doesn't fit, use a bigger hammer!"
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