If so, it's a switch to get better audio but when it fails, you may get no audio. This can be an actual switch or a component in the design.
If it was dirt I'd look at my camera bag. Is it clean and a fresh desiccant pack in there?
Bob
Hello! I had to have my Canon Rebel XS repaired because the phase switch was dirty. What is that exactly and how do I keep it from happening again? {It wasn't a cheap repair...}
Thanks!

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