Speckled material noise artifacting.

Was hoping someone might have some insight into why this phenomenon is occurring for us for some of our renders (The materials on the side walls are extremely distorted):


https://s3.amazonaws.com/static.havenly.com/dev/assets/preview-render-57497-3303526-EFED6AD2DC311B4A91AAAAB770DD0CE9.zip
StitchedExport.vrscene is the source.

Any pointers would be appreciated.

Regards,
Joshua