Every time I export my multicam mix from Premiere there is something wrong - sometimes there are one or two cameras missing, newest issue is effects/color grade being toggled on and off on a random basis. I know that one should not update right away when a new iteration of a software comes out, but somehow I found myself working on a 2021 version and I can't go back to the 2020 version because there is no backwards compatible format option on Premiere. What should I do know?
Update on the issue: I have a source video that I have multiplied on the timeline and scaled in a thus creating a budget multicam video. Now the issue seems to be that Premiere v15 at some point refuses to read scale and position data and it appears as original footage in the multicam view, but it reads color grading input. Having tried what I can thing of: toggling layers on and off, restarting Adobe and my computer, going back to previous versions of my project etc, nothing helps.
I have no real solution to your problem but am hopping onto this conversation in hopes that Adobe might do something about this or my findings help other lost souls with their mountains of bugs.
I had so many problems with a multicam project aswell (in PP 2021). Used mxf with AVC-Intra 100 (it was TV project) on a Win10 HP Z8 workstation and it was an absolute NIGHTMARE. I had a new issue every other day. Worked with proxies, which PP would regularly unlink. I could not bulk link them, what was - you can imagine - extremely time consuming relinking each clip individually.
The app would crash at least 10 times a day, for example with the import function, or projects would get corrupted regularly. The go to troubleshoots would give me 1-4 hours of uninterrupted workflow. The last nail in the coffin was the "frame substitution recursion" error. PP told me suddenly and out of nowhere that my files (and all of them at that!) had missing frames. Proxies would show, but the moment I disabled them there was only black screen. No hi-res export possible, since Encoder would abort because of missing frames. Nothing I read in the forums worked and I didn't have the time to to re-transcode 3 TB worth of material to see if that would help. Since the files played perfectly in Davinci/VLC.
I imported one timeline into PP 2018 (12.1.2) via xml. Appearently Adobe introduced the "frame recursion" feature in 2019 and I had read in the forums that people had this problem with 2019 already. And it worked! I don't know if "working" is the right term for an app you pay 250+ bucks per year, but none of the above mentioned problems occured. This meant that I had to import all my progress so far via xml and as you know that format doesn't support multicam so I had to manually redo all the edits. A true FML moment right here.
To me this means that Adobe rolls out newer versions prematurely. Although this is a kind of known fact in the editing community, sometimes a client wants you to work on "their" Version of PP because of compatiblity or because a previous editor started the project on a newer version. And that's really a bummer. Furthermore Adobe doesn't offer standalone downloads of e.g. 12.1.2, only the first build (and what did we learn? First build no good). So you have to be lucky to have saved the installer package.
I don't know why but clients love PP, so I am stuck with this program. I'd rather transfer my material on celluloid and edit it on a Steenbeck then doing another project with PP again - but, here we are. So please Adobe, less flashy new features nobodies needs, more stability.