I guess you mean that I have to ground all channels I use? I was under the impression that I could use a setting on the TBX-68T terminal block to ground all channels - also, I think the virtual bench gives that option!
am I right? do I really have to ground all individual channels?
You are correct that you shouldn't have to ground reference these
channels manually. It is actually the NI 4351 that provides
programmable ground-referencing. Page 2-5 and 2-12 of
the 435x User Manual describe this in more depth.
Am I correct in assuming that you have already tried to enable this
without success? If this is the case, then one thing to make sure
of is that you have configured the NI 4351 as having the TBX-68T as its
accessory in MAX. To do this, right click on the NI 4351 and
choose "Properties" and choose the TBX-68T as the accesory. Do
you have this set appropriately?