Hello Thom_H
Which measurement mode are you using?, cyclic mode?
Could you check the BAL_GLOB_CFG and BAL_CH_CFGx registers, are you clearing them after each measurement?
I recommend you refer to the following community case:
MC33774 cell voltage errors
It has useful information and also explains how to access two very useful documents: MC33775A and MC33774A measurement and Errata sheet for MC33774A
Both are secure documents, so your company must first have an NDA with us.
I hope this information has helped you, please let me know if you need help with anything else.
Have a great day and best of luck.