Layer brightness/opacity random flickering error at 4k

[ciaranl76720475]

I am getting a random flickering on certain layers across multiple compositions in my project, making my work unusable.

Comps are 4k, about 20 layers. About 10 layers of pre-keyed smoke footage, pre-rendered with opacity. These layers are fine when viewed individually. Once all the work, effects, masking, etc is applied layers start flickering randomly. E.g. one smoke layer might go about 50% darker for 1 frame throughout the whole comp. If I preview on this frame, I can make it behave normally by changing something - like position, or turning off an adjustment layer, tweaking curves, etc - then it will flick back to normal brightness. But there will inevitably be some other error pops up elsewhere, which behaves similarly - and again, fixes itself in response to a random adjustment.

It's nothing to do with keyframes I have added. 3D is off. I have updated drivers, cleared cache, etc.

And here is the super-annoying thing.  If I make a new comp at 1080, and put the 4k one in, and shrink it to fit, the flicker goes away.

What's going on?

Hardware:

Processor AMD Ryzen 9 3900X 12-Core Processor

1080Ti Graphics

64GB RAM

Footage is on M.2 drives

Is this setup really too slow for a 20-layer 4k comp??

[ciaranl76720475]

I should also say that in the 4K comp, the flicker is there both in preview, and upon export. It is consistent at whatever resolution preview is set to - full, quarter, etc.

[ciaranl76720475 · Accepted solution]

I know the whole Adobe Support Community is holding their breath in anticipation of a solution... I FOUND IT!!! So I'll post the solution here in case anyone else has the same problem.

I have a working project M.2 drive where I put my AE projects (and usually intermediate proxy renders and, and a seperate M.2 drive for footage.

On this project however, I had my main footage on the 'footage drive' but my pre-keyed smoke layer footage on the project drive. When I moved the smoke footage off the project drive onto the other drive and re-linked, all problems went away.

It is worth noting that I was having problems even in compositions without any reference to this footage.

So there you go. You're welcome Adobe.

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