I am putting together a video compilation that consists of about 50 or so movie clips, each trimmed down to about 10-20 seconds of video and then sped up to 8x speed. I have one music track that plays throughout it. (It is a timelapse of our son over the past two years)
Recently, the file has started causing me issues when trying to view the preview. When I play the preview, the video will slow down and get choppy for a second, and then skip ahead (by 20-50% of the video length) and freeze. The music continues to play, and when it catches up with where the video is frozen, the video resumes and continues until it happens again.
This only happens on this file. If I publish the video, the published version does not have this issue. I have a copy of the same file from 1 year ago, before I added another year's worth of clips, and that one still works fine. Other video projects don't seem to have any issues. This makes me think it is something about this file specifically.
From other forum posts I have read, I suspected hardware issues, but the problem occurs on my computer and my wife's laptop, and when I look at resource usage there is plenty of spare memory and cpu capacity. Additionally, playing the preview on all of the lowest settings with hardware acceleration off doesn't seem to help at all. I have switched just about every video setting on and off to see if they were causing the issue. At this point, I don't believe it is a hardware capacity issue.
I have tried the following:
Re-importing the video clips.
Starting a new project and copying and pasting the timeline into it (issue occurred in new video as well)
Deleting sections of the timeline to try to see if any particular clip, transition, etc, is causing the issue (no effect)
I really don't want to re-do all of the work I have done on this project - I did a lot of trimming and editing on it before the preview stopped working.
Does anybody have any idea what might be causing this and how to fix it?!? Thanks!