A curious issue with OBS 26.0.2

[npnandakumar]

I have been doing the following in OBS 25.0.8 without any issues:

• Screen recording video1.mp4 and video2.mp4 using OBS
• Replacing the audio track of video1.mp4 with audio.mp3 using the command ffmpeg -i video1.mp4 -i audio.mp3 -c:v copy -c:a aac -map 0:v:0 -map 1:a:0 video3.mp4
• Concatenating video2.mp4 and video3.mp4 using the commands (echo file 'video2.mp4' & echo file 'video3.mp4' )>list.txt and ffmpeg -safe 0 -f concat -i list.txt -c copy output.mp4

I could play output.mp4 without any troubles. However, after the update to 26.0.2, I am having trouble with the procedure. There is no problem with individual files video1.mp4, video2.mp4, and video3.mp4, but when I concatenate video2.mp4 and video3.mp4 the issue pops up. The video gets stretched by a few seconds and the audio playback becomes slow.

Because of this issue I had to go back to 25.0.8. Any idea what might have gone wrong in the new version?