Weak Companion/Right Channel on Monoblocks

[MusicFirst]

Today I tried swapping the left and right channels on my D400s by making the master output the RH channel information and the slave output the LH channel on the configurator, then swapping speaker connections, so I effect I was using the master to drive the RH speaker and the slave to drive the LH speaker.  My CDP is still connected to the master via SP/DIF Digital 2 and the master and slave are connected via my Audioprana hybrid SP/DIF-AES/EBU cable.

At the request of Devialet support, I also disabled SAM and set my tone controls to zero.

With this setup, one would have expected the RHS characteristics to have manifested themselves on left channel in some form, and perhaps some of the relative LHS characteristics to swap channels as well.

Amazingly, The subtle weakness on the RHS was still there.  

I had assumed that either the link cable or the slave unit would be to blame, but this is clearly not the case.

Once again, setting up the Master as a D200, the slight loss in presence and detail on the RHS with the D400 was gone, and a more coherent stereo presentation existed.

Any thoughts or similar experiences?

Thanks

Kerry