I just heard back from NI regarding the missing samples bug: "We are aware of the issue you are facing with battery 4, as it is a known bug. Our team is actively working on a solution and we expect to release a fix in the near future."
However, an internet search shows that the missing samples bug has been around since 2011! Why haven't they fixed a 13 year old bug?!?
This is frustrating and disappointing. I have spent thousands on NI products because they sound great and are good to work with, so this anomaly is very grating.