Sensor sync and control mode reliability

We have been having some reliability issues with synchronising config and setting control mode from both Eos (3.0.2, 3.1) and Concert (4.1.1). It seems like this issue started when we updated CEM3 to, but I can't remember where we moved forward from now, probably 1.7.0.

It can take 5/6 attempts to change control mode from either method. Even when config does finally 'stick' we are sometimes seeing out of sync issues.

Any thoughts?