Fraid to say that 10 degrees off is a concern. 2-4 is not. Unfortunately the Digital is not capable of calibration (however, the Total Control model is).
With this temp difference, I would recommend contacting the factory and arranging a service call, or having the installer check it out.
Things to verify:
1) Sufficient flow to the manifold - check the bottom manifold check valve to ensure that the check valve is closed when the pump is off (indicated by the red gasket on the inlet side of the check valve moving all the way to the influent side), and that the check valve is opened about 1/8" to 1/2" when the pump is on.
If the check valve is stuck opened, there may not be sufficient water flow to saturate the tri-sensor, which can give a false temp reading.
2) Tri-sensor cord is securely connected to the tri-sensor - remove and inspect for any debris and make sure when reinserting, that you align the two components (there is a groove on the tri-sensor that aligns with a keyway on the tri-sensor plug.
3) While the tri-sensor is off, inspect the tri-sensor pins. There should be 6 pins that are straight. If you do not align (as indicated in #2), you can bend a pin.
4) Run a TEST POOL PILOT and let me know what the CELL AMPS and VOLTS show - if the display shows lower than the normal range, it can indicate that you have 110 volts wired to the unit (factory wired for 220 volts).