Actually i continued mining with two miners config and i got higher speeds confirmed by pool i'm using.
Strange, but it looks like it really works better that way.
I'll continue monitoring and report back later.
I'm interested to know your findings since I'm delaying the upgrade to 11.7 until more information on the (supposed) bug has been collected.
Glad it works for you though.
Just out of curiosity... is your CPU usage high now that you've upgraded ?