This is the setup
2 Cabasse Murano Alto and 2 Cabasse Santorin 30, the sub on the left is the new addition and has integrated EQ, the one on the right is nearly identical without integrated EQ.
The best bass response is on the left side of the room, most likely the culprit for the bad bass response on the right is the window. With only one sub, I was using the left position with the best bass response and cutting mains at 70Hz. I'm busy retuning now...
The subs are also connected to the subs out of the Marantz for multichannel, so the crossover can only be managed by the NAD and the Marantz.
I thought that the subs out of the M33 could be used in stereo since they are measured and EQed independently by Dirac.
Also based on these observations:
https://www.audiosciencereview.com/...-m33-streaming-amplifier-review.17302/page-42
However with Dirac and both subwoofers running in mono it's already an improvement.
See below how Dirac aligns the subs on the mains: