MAX! Cube strange behavior - setpoint does not arrive at the thermostat

currently I have a very strange behavior:
I send a temperature setpoint to a MAX! thermostat but the setpoint never becomes active.
The new setpoint never arrives on the physical thermostat.
The thermostat always shows the setpoint which was adjusted locally.

This is on all devices / thermostats.

I am running a clean install of OH 4.1.
I have done a factory reset to the cube and freshly learned all devices on the cube.
The devices accept setpoints from the cube itself - I tried for testing. Normally I use the exclusive mode in the binding.

Even in trace level of the MAX! binding there is no error in the log’s.

2024-01-06 12:55:11.654 [INFO ] [openhab.event.ItemCommandEvent      ] - Item 'MaxThermostatWigaSetpoint' received command 18.5
2024-01-06 12:55:11.729 [INFO ] [penhab.event.ItemStatePredictedEvent] - Item 'MaxThermostatWigaSetpoint' predicted to become 18.5
2024-01-06 12:55:11.743 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'MaxThermostatWigaSetpoint' changed from 19 to 18.5
2024-01-06 12:55:28.760 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'MaxThermostatWigaSetpoint' changed from 18.5 to 19

Have you found a solution? I have the same issue ([max] Can not change temperature via openHAB).