Hi @OUS
Welcome to the Premiere Pro forums! We are glad to see you here. We need a few more details to try to help with the issue. Please see, How do I write a bug report ?
Is the sequnce being selected when you atempt to pull down the menu for modify Audio Channels? I have attached a screenshot of what I can see on a Mac based system fo selecting audio channels. I do see your options are greyed out.
Thanks for submitting your bug report. I hope we can help you soon. Sorry for the frustration!
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