Screen Recording Timecode Not Sequential

[sshaw]

Version

v2026.3

macOS Version

macOS 15.5

What happened?

Recorded a few screen captures, concatenated them with ffmpeg, and uploaded them to YouTube. The concatenated video worked locally on QuickTime and VLC but on YouTube the audio track was out of sync and the video itself looked to be missing frames.

Long story short each screen capture had an invalid timecode so when I concatenated everything got messed up. QuickTime and VLC apparently correct this on playback but not YouTube

What did you expect to happen?

No response

Steps to Reproduce

1. Capture a video
2. ffmpeg -v warning -i ~/Movies/BetterCapture/BetterCapture_2026-07-08-22.46.04.mov -f null -

This produces a ton of warnings:

[null @ 0x15c1065b0] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 1 >= 1
    Last message repeated 5 times
[null @ 0x15c1065b0] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2 >= 2
    Last message repeated 2 times
[null @ 0x15c1065b0] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 4 >= 4
    Last message repeated 1 times
[null @ 0x15c1065b0] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 5 >= 5
    Last message repeated 4 times
...

Video Codec

H.264

Audio Codec

AAC

Container Format

MOV

Alpha Channel

None

HDR

None

Content Filters

• Show Cursor
• Show Wallpaper
• Show Menu Bar
• Show Dock
• Show Window Shadows
• Show BetterCapture

Microphone

Enabled

I confirm that:

• I have searched existing Discussions and Issues and this is not a duplicate.

[jsattler]

Thanks for reporting. I will take a look in the coming days.