I have a strange problem we have a Laserjet CP2025 that has a colour deterioration problem, It will print ok for a while then suddenly the page output will deteriorate dramatically, sometimes just printing occasional patches of one colour and on other occasions the output looks like liquid spilled across a water colour painting.
If I carry out a system reset the monochrome will start printing, then after a second reset some colour will return but with streaks, each reset after this gradually improves the output.
See attached PDF