Basic Information Please provide a descriptive title for your feedback: Unable to decode mp4 video using AVFoundation on iPhone 11 Pro Which area are you seeing an issue with? AVFoundation What type of feedback are you reporting? Incorrect/Unexpected Behavior Description Please describe the issue and what steps we can take to reproduce it: Receiving decoderNotFound -11833 when trying to decode a 1 second mp4 video using iPhone 11 Pro currently on iOS14 beta 5. On other devices it works without a problem. It happens specifically on iPhone 11 Pro and iPhone XR. Have 1 second mp4 video use copyNextSampleBuffer check the status of assetReader; it will be .failed Expected to see images on screen The image is not displayed. Everything is grey More details Error Domain=AVFoundationErrorDomain Code=-11833 "Cannot Decode" UserInfo={NSUnderlyingError=0x280c94510 {Error Domain=NSOSStatusErrorDomain Code=-12906 "(null)"}, NSLocalizedFailureReason=The decoder required for this media was not found., AVErrorMediaTypeKey=vide, NSLocalizedDescription=Cannot Decode}