This document describes an issue where some macOS exported MP4 or MOV files when processed by Kaltura MediaSpace will have silence at the start even though there is supposed to be audio.
Some macOS Powerpoint 365 users have experienced this issue. We have not been able to identify the common thread between the users that causes the issue as it does not happen to all users.
This issue is present as of 5/8/20. Technologists are working with Kaltura and Microsoft on the issue.
- Load the macOS Powerpoint 365 file in Windows Powerpoint 365 and re-export the MP4 video file. This file will be processed correctly by Kaltura MediaSpace.
- With the media open in Kaltura MediaSpace click Actions → Launch Editor. Click Save a Copy. Name the copy of your media and click Create. A new entry will be created that should have the audio processed correctly.
Technologists have identified one case where it did not. In this case two users collaborated on a file and recorded audio using different microphones. In this case the only workaround was to load it in Windows Powerpoint, export it as an MP4 there.
- We normally recommend users upload media to Kaltura MediaSpace, but users can upload an affected MP4 to Canvas using the Record/Upload media function if your file is under 500MB.