Basically, I was editing 5 very long videos, about 1h20m each. The problem was after exporting those videos. The sound was normal for the first 40 minutes, and after that, it became muted to the end of the video!!!
Normal stuff, the original does have sound. However, at exactly 40 minute mark of every single exported video got muted without any reason, I didn’t even touch the soundtrack.
This is a bit vague…
As a start, can you provide a screen capture of your Shotcut window, with the playhead positioned at the exact moment the sound gets muted in your exported video?
Do you have sound after the 40 minutes when playing in shotcut? What about if you make a 10 second ranged marker after those 40 minutes and export only that part?