If you are getting a loss of power as well, Id guess it would be more electrical / sensor related than a clutster issue.
Cluster gets its info from the ecu which gets its info from the sensors. If the sensors are working correctly, the car should run ok, but just the speedo clutser be effected.
If you are getting a loss of power also it could indicate that a sensor has an issue.
Unfortunatly, with most new cars you need to plug them in to find the problem. £100 diagnostics could be cheaper than chaning a few parts that turn out not to be he ones at fault...