If during a game, it turns black and freezes, it's possible that it may be due to a hardware issue. Please take the following steps and this should help solve the issue:
Make sure the VR headset HDMI is connected to the display port and not the motherboard port (click here for an example)
Make sure your Guardian is set up correctly and you have enough room around you. Try resetting the Guardian and creating a new one
If the issue is not fixed, try uninstalling and reinstalling BoxVR.
NB: If you’re using Quest Link with an unofficial/unsupported video adapter this may be the cause of the issue.
If the above solutions do not work for you, please do get in touch with us directly at support@fitxr.com