This is something that’s been happening ever since I first installed the program. Occasionally, when I’m playing a section of the timeline back to look it over, the playback will stop. Half the time, it’ll just pause where it is, but the other half of the time, the line will jump all the way back to the start, and I’ll have to find where I was again. I originally thought the problem was that some of the files I was using were on an external hard drive, but it happens when all my files are on the main drive, too.
Shotcut ver. 19.12.31
Here are my PC specs:
Windows 10
Intel® Core™ i7-7700 CPU @ 3.60GHz 3.60 GHz
16.0 GB of RAM (15.9 GB usable)
64-bit Operating System, x64-based processor
It could be that your video is not “seek-friendly”. Have you tried converting your video to “edit-friendly” before processing? This is just a guess as I have not come across your problem myself. See also the post here: Why is Shotcut playback so annoying?! (Shotcut 18.05.08)
Same issue here, Windows 7, Shotcut version 19.12.31, and I’m using Bilinear Interpolation reading from an mp4.
I should also mention that this also occurs sometimes simply when navigating between clips on the timeline using Alt + < or >.
Another trigger seems to be just appending or inserting a clip to the timeline. It seems like anytime it scrolls past the current end of the viewport, it wraps back around to the beginning and there’s a chance the playhead will actually move there.
Other times the playhead will just stop at the end of the viewport, even though the player still indicates it’s playing (shows a pause button instead of play).