Hi Gary,
Thanks for the feedback. Keep us posted and we will see how best we can resolve. As mentioned, spec wise the amplifiers are fairly similar so perhaps we are dealing with a subtle setup issue.
Some other brainstorming, the voltage divider scaling is about 30% higher on the DRV8323 EVM due to the extended voltage range of the device. For low inductance motors the back-emf will contribute significantly to the observer error. It may be ideal to match the divider ratio or even adjust it to be more suited for your 24V operation range.
-Nick