I noticed that for some of the sites when streaming videos at 4k on iOS there is only audio and no video. I tried downloading the files directly on my phone to see if it would resolve the problem but that didn't help.
The native iOS media player also has the same issues when trying to play the downloaded files. I was however able to play the videos fine with the VLC player app.
I transferred the apps to my desktop so I could inspect them further and realized all the impacted videos are using the H.265 sub-codec hev1/hvcC . This seems to be a known issue for iOS devices (link).
Video
ID : 1
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main@L5.1@Main
Codec ID : hev1
Codec ID/Info : High Efficiency Video Coding
Codec configuration box : hvcCHere is the information from my settings About page:
Version : 2.2.9(357)
Device ID : 13673D89-3D70-4C1E-BF5d-C7ZC3BBE202A
Hello,
Thank you for contacting us. PLAY'A VR player uses the default video player and cannot implement VLC. Unfortunately, we cannot fix issues related to the standard video player. However, our team will look for possible solutions in future updates.