MatteControl contract/expand issue

MatteControl tool's Matte Contract/Expand sets entire alpha to 0.0 when the value is different from 0.0. In other words, as soon as you move the slider or type in a value different from 0.0 the alpha goes black.

Build 15.0.0B.037
Windows 10 Pro

It works as expected for me. Possibly a GPU issue?

Resolve 15.0.0b.037
Windows 10 Pro
GeForce GT 420, driver version 388.13

Yes, I noticed that.

Depending on the source DNXHR, Prores 422, Prores 4444 or MP4 (with ALPHA Premultiplied), the reaction of the MatteControl tool's Matte Contract / Expand reacts a little differently. It is very very sensitive.

I admit that I do not have 100% Master to control over the MatteControl tool's Matte Contract / Expand combined with a mask tools but it's quite subtle ...