Pinhole alignment on Leica TCS-SP5


Does anyone know if it is possible to align the pinhole on a Leica SP5 confocal microscope? I find a substantial drop (>50%) in signal going from 2AU to 1AU. I think Leica told me pinhole alignment was only possible by a service engineer but due to the age of the system if I am able to do this myself I would prefer to.