Flow works speedo problems
 

Hi,
I've got an LRP Flow works esc that has been working faultlessly up until recently. The problem is that the steering servo (xpert WR4401) now operates at an extremely slow turning speed making the car un-driveable, I've tried another speedo and the steering servo is fine normal operating speed, I've also tried another servo on the LRP speedo and again it turns extremely slowly so I know it's not the servo. Is it possible for the BEC circuit to fail and it's output be reduced giving less than 6v to the servo? If so, is it repairable?
Thanks for reading.