I already have another Thread open at the moment (RTX 3090 memory errors) but while trying out Arnold 4.1.0 to circumvent the issues I had with that card, I noticed a more serious issue then the little annoying GPU not doing exactly what it should ;)
When using UDIM tiles (well not sure if there's any connection, but they are UDIMs in this case) in MtoA 4.1.0 parts of textures will randomly be missing. This will not happen in other versions of arnold. This happens in a mix shader (texture input is fed into the mix of the…mix). The part might render on some frames and not on others, when running the IPR they might appear or not appear. This seems to happen on RTX 3090s as well as a 1080.
Here are the Screenshots. The "9" (Which is on the same UDIM tile as other the parts of the tail number of the plane) will randomly just go missing. Also other parts of the texture.
I can provide a file (full project) for investigation tomorrow if you want to have it. Sorry for starting two threads, but it seems to be one of those days where issues just magically appear out of thin air ;)