I never had the issue because I do not use audio alerts and have them turned off.
Everything is working fine and I have not had any closurers of the callsign window.
I'm on the air all day and make between 80 - 125 digital contacts per day without having any problems.
I can only guess that because I have the audio alerts turned off, I have not experienced any issues with the latest MS updates or with JTALERT.
If I turn on the SOUND alerts then I get the crackling noises and other problems.
I turned them back off, stopped JTA then restarted it and it's back to working normally.