Code review comment for lp:~yuningdodo/unity-control-center/unity-control-center.lp1396464-prevent-update-sink-input-in-parallel

I updated my patch. After more debugging I found there seem to be an unneeded trigger to the frontend update, this update will finally lead to the reported issue.

I reverted all my previous changes and then only disable this trigger, in my tests the issue is no longer reproduced.