That doesn’t sound good.Any chance we can get a copy of your project and source so we can attempt to reproduce in-house? See instructions below for how to do that.Thanks.
In the Project panel, select the composition that contains the footage with Roto Brush applied.
Go to File > Dependencies > Collect Files
In the Collect Files dialog:
Set "Collect Source Files" to "For Selected Comps"
Enabled the "Reduce Project" checkbox
Click "Collect" and select a location to collect the project file and footage
Zip up the folder containing the newly-collected project and footage.
Add the .zip to your Creative Cloud storage ( or Dropbox, OneDrive, etc ) and email a link with a brief description of what you were experiencing email@example.com. All footage submitted will be kept confidential and will not be shared with third-parties.