Fixing Sources That Only Display Black
If display issues occur when trying to add a video file as a source, try the following:
Go to Tools > Settings and on the Advanced tab, switch the option from Prefer CPU for video processing to Prefer GPU for video processing.
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Go to Tools > Settings and on the Advanced tab, uncheck Use Media Foundation Engine for video playback.
This option is only available if you have your Video processing mode set to Prefer GPU.
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Solution 1
Go to Tools > Settings and on the Advanced tab, switch the option from Prefer CPU for video processing to Prefer GPU for video processing.

Solution 2
Go to Tools > Settings and on the Advanced tab, uncheck Use Media Foundation Engine for video playback.
This option is only available if you have your Video processing mode set to Prefer GPU.

Updated on: 11/08/2022
Thank you!