Swatches: CMYK color icons occur RGB only

[thomaso]

In the Swatches panel the squared color preview icons of a CMYK palette appear in RGB look even in a CMYK document.

In this sample especially the 100c (last icon) occurs disturbing wrong and the 5 green swatches are hardly to distinguish – very different to the objects with these fills:

I can not recognize under what circumstances this occurrence happens. It doesn't occur all the time. It is not related to a specific .afpub.
(This swatches false RGB-ish look was reported in one of the betas before retail version already).