Cellwasher2 with improper saline fill

I have tried everything according to the service manual: The saline volume is correct (43ml), the distributor and cannulas are clean, the tubes are correct,  I have replaced all of the tubing so nothing is crimped / cracked or clogged, I have ensured the cellwasher is level, the rotor is not bent, nozzle is not clogged and it is level. The tubes end up filling at different levels, with no rhyme or reason...some almost overflowing, others half full. Anyone have any other ideas I could try (other than buying a new machine)!?! Thanks!  Mike,