DPX file with Alpha - Silhouette is adding banding

I have a DPX file with Alpha that displays normally in AE, but when I run it through Silhouette I get banding in the transparent areas. Setting the Input Mode’s Alpha Type as Straight or Premultiplied doesn’t eliminate the banding. Is there a “correct” way to avoid the banding?

It’s probably a variant of DPX that Silhouette is not happy about. Save it as a Tiff or EXR instead. Feel free to send me a single frame of the DPX file and I will take a look at it.