Hrm. I mean, I can monitor my memory usage and trigger it again, but I would be a little surprised if I ran out of RAM at 64 GB of RAM.
The ways I can easily reproduce the issue is either re-encoding a half hour long recording I made on my phone (1080p/60, I think the source codec is x264) or ripping a 4k BR that I own (so… 4k/24 at whatever codec 4k blu-rays use). I’m pretty sure ffmpeg is in use either way.
I haven’t checked the health of my RAM recently (the last time I did would have been around nine months ago), but I have checked my SSDs more recently - no issues there, and I can encode video to any of my four SSDs and still reproduce the issue. I’ll do some memory testing overnight to check that out.
Thank you both for help with troubleshooting, by the way!