Ok, settings seems ok. Like Mika said, 2x psu have to be very close in voltage, I suspect the 0.5V is perhaps to big gap…this has been known to cause this particular issue on some units.
Quite rare, but it has been reported (and fixed)
Oke, Thank you very much for your quick reply. I will write a support ticket. Hopefully this will fix my problem.
Mika can probably elaborate more on the workings of their power management with the two but what generally will happen is that a system where it sees that one power supply is not performing quite as well either in Voltage or Current Draw will bias toward the better one… The Unfortunate thing with this biasing is that when it does the Voltage will OK to run the SimuCUBE but the Current flow available to the SimuCUBE will be cut in half… This is when the shutdown occurs because the one PSU is not capable to supply enough wattage to handle a high power event, it then goes into shutdown, when it goes into shut down it will generally bias back to the other PSU and shut it down as well causing complete shutdown… When the PSUs are well matched the System will see them as one unit and draw from them accordingly. This was probably (speculation here) one reason why the v.2 Pro units have moved to a Single PSU since a single unit is MUCH easier to manage.
could the use of a redundancy module fix the problem ? theoretical question though.
Thanks Bsohn for the explanation 
Hi Mika,
I received a replacing PSU that schould be 47.7 V, but I measured 47.8 V (perhaps diffenerence in measure tools, maybe mine is poor quality) So one PSU is now 47.7V and one is 48.8V.
However… I am very happy with it now as I can race, hit kerbs, crash, make it very strong etc without problems! After some races, no restarting issue anymore! Thanks you for your great support and solving my problem The previous 0.5V difference was too big indeed, the 0.1V difference works perfect!
I faced something similar lately with my sc2 pro, as well. In most sims I play, when I crashed or went really rough over a curb it would just turn itself off, consistently. It didn’t happen before, but it’s probably related to the power delivery in my apartment, or my power strips.
I ended up turning the wheel force down to 50% in most TD profiles (I used 100% before), and I no longer have problems. Since I barely use the wheel force to that extent anyways, it did not really bother me to tune the force in TD down. When I crash now the forces are clearly weaker, but it’s not like it matters or I’ll be holding the wheel to find out anyways 
Driving it does not seem to show any significant differences, as I thought initially
Correction on the above: 48,8V and 48,7V off course (don’t know why I wrote 47.7 and 47.8) Still perfect and happy, no failures no matter what! Really enjoy it now.