From the answer, that Ketron returned to Roel, I got the feeling, that they are not quite aware of the problem.
I suggest, that we gather a few exact examples-styles that make us trouble, than we send them to Ketron to help them identify the problem.
My example:
Style Partybeat1+ Zivago and 2nd voice (Strings1) for right hand
- in Rel 4.0a eating Bass and even drums (especially after FILL)
- in Rel 4.0b eating right voices, sometimes Bass too (especially after FILL)