AVPlyer object play .mp4 video,has audio but no image.

AVPlyer object play .mp4 video,has audio but no image.

I use AVPlayer object to play .mp4 video, but has audio no image in iPhone OS version iOS 14.0.1 (not simulator) and Xcode version 12.0.1.

I find this issue that show new Xcode 12.0 over version, and I download Xcode 12.0.1 version,Xcode 12.1 GM seed version.It's very serious problem,I can't play video.
If this was working on previous versions of iOS, please file a bug report using the feedback assistant. If possible, include a sample app we can build and run to reproduce the problem, including the source .mp4 file you are using.
AVPlyer object play .mp4 video,has audio but no image.
 
 
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