I am not sure why it is happening now, but moving cables around, database and using the DBB class I came to the conclusion the hardware is ok.
I will send a mail to Ole and try to look into it to fix the issue. So far my work around is to instantiate another vdc for the right arm and put u1 in all the planes of this vdc, so look at v1,u2 or v2 allows to see all wires of u1.
So the symptom is u1 does not display anything after wire 304.
Figure 1