AE200 central controller Mitsubishi fault?

I'm having a problem with an AE200 central controller.

It has 4 vrf system wired back to it on separate floors. On one of the floors there are 20 or so fan coils run from 2 x hybrid bc boxes.
On this particular fl only the controller will display 4 or 5 of the fan coil icons as an orange icon. This i would usually understand as having lost communication with the fan coils. When I open the icon it I seem to be able to control the fan coil and the icon will change to a normal green color indicating it is running. The customer see's orange icon and assumes a fault but no fault light flashes on the controller.
So the normal color is grey for off and green for on.
I spoke with Mits tech and they said do a master reset ie start up sequence of indoor/outdoor/ bc boxes. this does normalise all the icons but within 24 hours they change back.
Any ideas appreciated