Audio issue with the video

[WastaTariq]

Dear Canvas 

This is Wasta, I am using Canvas app which my school provides me to takes the video lecture but on my Ipad (IOS 15) generation 8 ,as I open the video there is no audio in the video , only when I start the video there is a sound but as soon as I forward it or rewind the video the audio disappears. I contacted the apple support system they said my device is working fine and everything is good to go from my side they asked me to contact the developer as this issue is specifically for canvas. 
Also I tried to take the video from safari, chrome, Firefox but I faced the same issue there as well no audio as soon as I forward or rewind the video. Please help me in fixing the problem I am so worried due to this.

Regards 

Wastatar30@gmail.com