I am experiencing the same issue with a 900 pro XBP9B-DMUT. The nodes are all solid until integrating this transmitter. I do the same all -model running in a sync sleep mode. The transmitter seems to drop the A0,A1, A3, D4 analog inputs values. Other times it is rock solid. Also 900 pro models have worked well.
I have reinstalled the firm XCTU 8071 firmware. Didn’t change a thing.
What is going on is that the module is in a sleep state for longer than the Sleep period set on the parent node. By doing this, the end device is removed from the Child table of the parent node resulting in the end device having to re-associate. To keep this from occurring, you must set the SP time to longer than the longest sleep time you are going to have your end device sleeping.