I have a client with a small vMix setup that includes the following:

1 - BMD Web Presenter connected via USB for Camera and Audio Capture
1 - AJA U-Tap HDMI connected via USB for PowerPoint capture

The customer has a computer that only has 1 PCIE X1 slot so I can't install a capture card. I am stuck with doing USB capture. They already had the WebPresenter so we are trying to work with that.

Most of the time everything works fine without problem but occasionally the U-Tap input freezes. I can right click on the input and click "Reset" and it works fine for a period of time. They stream to both Facebook and YouTube but they don't stream everything to Facebook that streams to YouTube. They stop the Facebook stream during the broadcast. It seems like maybe the U-Tap freeze happens after stopping the Facebook stream although I have not tested this myself yet. The Facebook stream is stopped by ending the live video from Facebook and I think they just let vMix error out after a few seconds. The client says they think the U-Tap freezes after that. I have asked them to stop the stream in vMix first and then stop the live video in Facebook to see what happens. I am wondering if the error condition in vMix is causing the U-Tap input to freeze.

I realize that capturing two devices via the USB bus MIGHT have something to do with this but I am not sure. The AJA U-Tap is a supported device on vMix but the WebPresenter is not listed although it works without problem.

Other than the USB 3.0 bus possibly being an issue is there anything else I should consider that might be causing the problem?

Thanks.