Summary
When you try to play a video on your iPhone 6S or earlier device, you receive the following error message:
"This device doesn't support this video format. You can listen to the audio only."
Cause
This issue happens because iOS for iPhone 6S or earlier device no longer supports the playback of certain video formats in the Microsoft Stream mobile app.
Resolution
To resolve this issue, try playing the video on a Apple device running iOS 7 and above.