GfD timecode error

[bratpop]

I converted a video from MP4 to MPG, and it plays fine, but when I load the MPG in GfD I get this error:
"Inconsistent Timecodes! SCR=1:56:54 AM sec. GOP=1:56:40 AM sec."

Here's the thing though. The SCR is the correct length. The GOP is wrong. When I demux it, it ends up as the GOP length. When I author this, the chapter starts are at the wrong places. Otherwise it plays fine, but obviously I want the chapters in the right places. If I load the MPG in GfD it uses SCR, which is great, except I can't add any audio tracks. I think I can trick it by renaming it as M2V but I'd rather not have to.

Is there any program that can fix the GOP so that it's equal to the SCR?

I tried demuxing in ProjectX and it drops GOPs all over the place, and leaves me with an M2V of the wrong length.

I tried to fix the M2V with ReStream but I don't know what settings would work, if any. None did.

[borax]

I would try other demux utilities (pvastrumento or dgindex). Only mpg files have an SCR, elementary m2v files only have GOP timecodes. As you want to add an additional audio, elementary files are required. I don't think a program that can fix the GOP so that it's equal to the SCR is even possible, as if there are errors in the GOPs, these can be somehow 'masked', but not 'repaired'.

[bratpop]

I used Cuttermaran to demux and it finally said it was the correct length, give or take a fraction of a second. However when playing, the chapter starts were still off.

[borax]

However when playing, the chapter starts were still off.

Maybe this is the same problem as here:
https://forum.videohelp.com/topic343245.html