Was having issues using wireless DLNA to smart TV past few weeks using MC21. It would start playback and with in 2-3 min TV would report back saying file type not supported, after reading the TV booklet (LG) the booklet stated the error fix was to use a wired connection, well this is not possible. I danced with TV settings and MC21 settings for past 2 weeks. Then today I realized I did not have this issue with MC20 so I reinstalled MC20 along side MC21 restored the backup for MC20, turned off MC21 media server changed settings back to- do not start on start up and closed MC21 and server rebooted pc just because and set up MC20 to be the media server and guess what....not one issue with playback!
So I don't know what or why or if this is isolated to my set up....just reporting what I have encountered.