Weird behaviour of compression

Simple image with different 3 channels after TC_Default or TC_Masks compressions mix together channels. Wtf?
It’s not “noise”, each channel have a litle portion of picture from 2 other channels
Before compression

After compression

It’s more obvious if you crank up brigthness
Grid in red channel, circular forms in green.
Only red channel is active

Welp… Anyone?

Hey ze0rb, this might belong in another forum or on AnswerHub if I’m understanding the post correctly?