Using external camera with mic, the mic is not received by Zoom? any ideas

Hello @parton11 - Thanks for reaching out to Zoom community. There are variety of reasons that might cause this such as audio configuration, third-party software compatibility, etc. Can you try "Zoom Audio/Video Test " which should help determine if Zoom is receiving the audio signal? 

hi thanks for replying.  I tried the test you linked to and yes the mic does work and replays my voice when I select Blackmagic Ultrastudio as the mic input.  

Does that mean its just working then? I have only gone of the audio levels in the Preferences section, I haven't tried an actual zoom meeting yet with it.  There is zero levels registering on the audio level meter when I have Blackmagic selected as mic input, and when I change it to internal computer mic for example, the levels are bouncing around as you would expect.

Yes I started the test meeting and it the test for picture, speakers and mic all came back fine. Is that what counts as a 'test meeting' or is there more to it?

sorry, I thought I'd resolved the issue but I haven't.  When the Blackmagic Ultrastudio was selected as microphone -  I now realise it was actually still using the internal computer microphone, despite still saying Blackmagic Ultrastudio in the mic select.  Then when I selected internal mic and then went back to Blackmagic it now has no levels for the Blackmagic external mic.

I know this mic is sending down the HDMI from the camera it is connected to as when I open Blackmagic Express its all perfectly fine in there. it just seems like Zoom is struggling to use it.  is there a driver I need to install?