M1 Mac here with videos ending in .mpg. QuickTime Player doesn't see the video portion of the video and there are eerie sound effects being played over the audio.
The problem is not limited to QuickTime but also affects video playback in PowerPoint. The real problem is that the user plays all his videos via PowerPoint.
iMac (M1, 2021)
My Intel Mac mini 2018 macOS 14.0 QuickTime Player plays MPEG2 and .VOB files OK. Maybe Silicon Macs behave differently or some 3rd party app interferes?
Anyway, I have found IINA a good replacement to view movies which are incompatible with QT Player. So try to set that as the default for such movies.
When I use QuickTime player, MPEG-1 videos don't play video and they add creepy sound effects on Sonoma regardless of the CPU type.
On a Parallels Sonoma VM on Mac Intel, MPEG-2 videos cause QuickTime player to completely misbehave, but I'm not sure how much Parallels is involved with that.
Unfortunately, Powerpoint uses the same engine as QuickTime player, so the MPEG-1 videos embedded in presentations cannot be played back.
Sonoma breaks video playback
