We're working on making 1SE encode these videos better but in the meantime there is a work around so you can still use these important videos!
Please download the free app Adobe Premiere Clip and re-export the video. 1SE will then have an easier time using it.
Download Adobe Premiere Clip here
Step 1: Make a new project in Adobe Clips of the video you want to use
Step 2: Pick from where ever your video is saved
Step 3: Select Freeform for the type of project
Step 4: Export the video (top right icon for sharing).
Step 5: Pick 1080p resolution
Step 6: Give it a minute to save it to your gallery
Step 7: Open 1SE and select a second using this new video!
All done! Your video should now save without any weird stretching or scaling.