Just had a strange issue while setting up for a very simple live show. Here's my setup -

Asus N53SV laptop
Single camera(HDMI) input via a BlackMagic Intensity Shuttle USB 3.0
Microphones were connected to the camera and embedded in the HDMI feed.
65Mbps Ethernet upload speed
Feeding the vMix output to Zoom Desktop Client running on the same laptop via vMix External Output.

Video in the Zoom feed is pristine. Audio is terrible. I've included a recorded sample of the audio.

To test, I also tried streaming to several different platforms including YouTube Live, Facebook Live, AudioVideoWeb.com and GoToWebinar. On all platforms the audio was perfect.

Thinking that it might be the Intensity Shuttle, back in the studio I've tried the same setup using my full desktop PC with a BlackMagic Decklink Mini Recorder(PCI), but the results are the same. Also tried a different camera, but the audio is still terrible. Tried different microphones as well.

We've had problems using professional cameras with another platform(GoToWebinar), and learned that the platform did not support professional camera use, only webcams, and we had ended up using ManyCam to fool GoToWebinar into seeing our pro camera setup as a 'webcam'. We tried that in this show, and it seemed to work well, the audio issue cleared up. However, since it was such a simple show, it seemed intuitive to eliminate vMix and just use ManyCam, which worked well.

I have a Magewell HDMI to USB device ordered. Curious to see if Zoom just doesn't like the feed from a BlackMagic device.

I'd love some suggestions on what could be the problem. The client had a corporate Zoom account, which comes with a Zoom Support person, but they weren't very helpful. zoom.mp3 (1,186kb) downloaded 6 time(s).

Unfortunately, that was one of the suggestions from Zoom Support and has no effect. I would have mentioned it, but truthfully, I lost track of everything that we tried.

Here's another wrinkle - I just tried plugging the microphone into my Zoom H6 connected to the PC as an audio interface(USB) created an input in vMix for it, and the audio is fine. So I'm narrowing it down. Seems as if Zoom doesn't like audio embedded in an HDMI signal perhaps? Can't wait to try my Magewell Capture device to see if it's BlackMagic specific HDMI input that Zoom doesn't like.