When an audio input is changed in windows, minecraft is still using the old output.
Minecraft needs to restart for it to use the new output.
Example:
Usually when i play Minecraft, I play on my speakers. But if someone calls me on discord while I'm playing, I need to change output device to headphones. Minecraft will still be using the speakers.
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-44055, which has been marked as Won't Fix - while this behaviour is not desirable, the developers have said that they will not or cannot fix it.
Please use the search function in the future to prevent duplicate reports.
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