OKI C9650

I have a Oki 9650 which is presenting me with a few problems.

I am running it from an iMac running OSX 10.6.8

The issues I have are:

-Ink/toner waste bin full warning when sending job to print (despite changing this item)

-my prints have a cyan speckling across the entire print area - I have checked and found no toner spillages or such like

Any ideas people?