Using the iFrame API, the audioMuteStatusChanged event is not fired when the user has been muted by a moderator. However, the videoMuteStatusChanged is fired when the video is stopped remotely.
In the subscriber.ts source, there is a listener for when the video is muted, but not one for audio. I did add one in there, which works, however the event is then fired twice when the user does the muting.