Hey , can someone help me setting up my Vega rigs for xmr mining ?

I had a perfect setup using xmr-stak-amd , with 1407/1100 settings, all cards reg modded etc.

Now with the new XMR-STAK I am facing following problem - all shares are rejected by the pool, when using these settings even with a single thread. Pressing R shows low difficulty share errors , wtf?

Oddly enough, I am getting all good results using the ETH settings I am using - 875 core / 1100 memory. Hashrate is significantly lower of course.

Any idea how to set this up right?