Is there a way to adjust MOH volume that the caller hears?
Off the top of my head, I can’t recall anything but then again when the MoH is too loud for me when I call some place, I turn the volume down on my phone. Or if it’s too low, I turn it up. While I’m all about my Rock’N’Roll going to 11, my phone doesn’t really need to so it’s generally in a low to mid-range anyways.
You can use sox to “normalize” all your files in /var/lib/asterisk/moh/
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