OBS Still Not Remuxing Larger Video Files

[DamnitDinkles]

Posted on the r/OBS subreddit a few weeks ago and didn't get any answers (Remuxing- MKV File shows levels in audio mixer but is not playing and giving an error when remuxed) to help with the OBS side of it, but now I know multiple people whoa re having this issue and we haven't figured out how to fix it, so I posted again to reddit and was also recommend to post here as well.

TLDR of the original post: MKV video file that is playing fine in VLC is giving an error when remuxed in OBS. "Remuxing finished: Recording remuxed, but the file may be incomplete". The remuxed file will not load anything, and the couple of times it has, it won't play audio. The mkv file in OBS is showing levels, but will not play them in OBS. I showed this to a friend who is a professional videographer/editor and confused the frick out of them. They tried to get it to remux and couldn't.

Update: The problem persists with the same details as above, but we've figured out that it is only doing this to mkv files over 1GB. Anything under 1GB will remux with no issues. My friend mentioned above began also having this issue on her iMac (vs me on a Windows 11 PC) and also seems to be based around mkv files larger than 1GB. I have googled and tried to find if there are any other posts about this issue and the only one I could find was "Videos corrupted if over 4 GB in size" but the computer I'm editing on has 16GB of RAM.

I work at a trade school based in technology and we have broadcast and podcasting classes. We use both OBS and Streamyard for students and graduates and one of the instructors has a production house. Just spoke with some grads who are now also having this issue on the computers in our studios, and that is on Windows 10 PC's. The instructor primarily uses Streamyard so hasn't noticed it yet but when I explained the problem to him, he explained multiple students/grads have also been having this issue.

Any help would be appreciated, both by me and a bunch of students/grads. Thanks!

 

[DamnitDinkles]

Bump

 

[rockbottom]

v30, I just remuxed a 25.4GB mkv, no issues here.

Check audio on the source mkv it must be AAC. If it's not, you should still be able to get it re-muxed using Avidemux.

 

[Lawrence_SoCal]

I've been remuxing 11GB+ MKVs to MP4 for years now, takes about 20 seconds... never had an issue

4GB seems like old file system issue with FAT... (not any application)
I'd start with basic OS level troubleshooting... is security software interfering? is file system appropriate (presumably NTFS, but worth confirming), is Disk I/O overwhelmed for some other reason? etc
Then, I'd look at the specific OBS Studio recording settings... maybe someone changed something at one point (for whatever reason), and that is the problem

In another recent thread someone complained about remuxing to MP4 and getting a MOV file instead. Turns out user was using custom recording settings (with PCM audio), that are incompatible with MP4 (PEBKAC).
granted figuring that out with FOSS isn't always as easy as with other software... price of admission, so to speak.

The other thought that crosses my mind, is that the computer isn't up to the task (with settings being used).. and can handle it for a little bit (1GB MKV) and then gets overwhelmed... or overheated/thermal throttling? and the resulting MKV has something interfering with remuxing to other format (with format compliance checks)

Do you have DaVinci Resolve onsite (which supposedly can handle MKVs directly nowadays)? have you used that or something else to check the MKV for issues?