While testing a softphone widget from Zulu, I called my own cell phone. When I answered the call from the cell phone and said hello, a feedback loop was created that started an ever increasing series of "hello"s being played by the computer sound and the cell phone's speaker. When I hung up the call subsequent calls to any phone number reveals that the microphone appears to be dead. However, the microphone continues to work fine for ms-teams and zoom but not via firefox and the zulu softphone widget. Rebooting, clearing cache, uninstalling the widget and reinstalling does not fix the problem. Where is firefox "remembering" that this event happened and refusing to use the microphone? Thank you, Greg