FYI:
I'm using an Avermedia Capture devices to connect a Sony camera to vMix via the LGP Lite Stream Engine driver. Having recently upgraded from version 23 to 24, I have noticed intermittent freezing of the camera input, at which point I would pull out the USB cable of the Avermedia device and plug it back in. This has become necessary because if I try to close the camera input to recreate it, the entire vMix app freezes. The current output continues to work but no mouse clicks are effective. The only alternative is a hard reset of the laptop. One other alternative to closing the Stream Engine input is strictly to ignore it and create a new input with the same source. Closing the input freezes the application. The hardware I use is an MSI gaming laptop with 16MB ram with 2070 graphics card.

Next option is to reinstall the Avermedia drivers and see if that solves the problem.