I have two logitech usb cameras and both have the same issues with audio in CA. I just bought a c922x because it can record 1080 video. CA with not allow audio capture with this camera even when you set the audio capture the same as camera which is 4100. This is more than a little strange because there are a lot of logitech cameras out there in computer land. Every other app I have that records audio works great with the logitech camera, if fact I have to turn down the audio in-put in the core because the stereo mic on the c922 picks up so good.
I have a scarlett 2i/2 on my desk and if I screw around enough I can get it to record audio in CA. The odd thing is that when I turn the scarlett on the camera is disconnected from CA. At this point I have audio and no video in CA. If I shut down CA and have the scarlett running with the camera, sometimes it works and sometimes it does not work. What it boils down to is a little tap dance flicking back and forth until finally CA will recognize both the camera and the audio. It is a pain in the butt because you have to change the settings in the core away from the c922 to the scarlett when working CA. If you don't have a separate audio interface I have no idea how your going to use CA at all. It seems that Adobe should at least list USB cameras that will work.
I like CA but have no idea why the engineers at Adobe have not addressed this issue, without audio the whole premise of the app is lost. I see articles all over Internet with folks looking for cameras that will work with CA. The puppets might dance and prance like magic, but without audio the production is a bust. One teacher was looking for twenty cameras on this forum and still did not get an reply that I could see from Adobe. I have a feeling to the boys at adobe set up CA for lap tops and forgot about the millions of us that use regular computers. Hopefully the brainy boys at Adobe can solve this problem soon.
I have an addition to the above comments. I said that the Logitech c922 mic worked on my other apps but not on CA. I was wrong, I tried a couple more after thinking about it. It did not work on one and guess which, 'Adobe Addition'? Adobe apparently uses the same audio architecture in both programs? To make my question from above clearer, I was wondering when Adobe might fix the problem? After pulling up 'Addition' and getting the same warning as in CA I think I got the answer to my question? That is most likely, never.
The apps I have that the Logitech c922 worked on were: Apple 'Photo Booth', 'Logic Pro X', and 'SwiftCrapture'. I do have one interesting note. Apples 'Image Capture' would not acknowledge the the camera was connected at all. That doesn't have anything to do with anything anyway, does it?
Not exactly sure of your question, but I can see you are having trouble and you are frustrated so I figured I would try to help.
I use a Logitech C930e and it works great for me. I also sometimes use a Lavalier for audio,
it makes a big difference in sound quality for sure! (and they are only about $20) and removes all the background noise and that sssshhhh and hmmm sound you get without it (but could be cleaned up using Adobe Audition, that works pretty well too, its like Magic!)
Are you clicking the Contextual Menu (3 lines in top right of the window) in the Camera & Microphone window and choosing your camera? That should work. And obviously your microphone icon is clicked and is highlighted in Blue, and not disabled and colored white?
The audio should be automatic, if I plug in my mic, audio is from my mic, and when I unplug my mic, audio is picked up from the camera, and when I unplug my camera, the mic on my laptop picks up the audio. Could it be a problem with the camera itself?
Sorry you are having problems, I know technical problems can be frustrating when all you want to do is CREATE!
Hope this helps and you get it working.