I"ve heard a few others comment on having this same problem so thought I would share how we fixed it.
This may not be everyone's same issue but could help some.
I have been having an ongoing issue where I can join a Spaces meeting but when I click in top right to join the audio/video meeting in progress it never connects. Unable to see any presentation or hear the audio/video. Work around is to dial into the meeting via phone however then can still not see the screen share. This was only on my work laptop, worked well on another laptop so figured it was a security setting of some sort.
It ended up being our internet security and web filtering system and specfically the *.mpaaservice.com. It was catergorized as Miscellaneous or unknown and therefore blocking the media piece to work in WebRTC. That is why I could join the meeting but not the live audio/video.
When we exempted *.mpaaservice.com from SSL inspection it worked. You could also pursue getting *.mpaaservice catergorized as "Web collaboration" as another option than exempting from SSL inspection. If you aren't part of their team, contact your IT security team and they can make the change. (may required an approval process)
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Lori Wodrich
Sr. Systems Engineer
Amerisure Insurance
Farmington Hills MI
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