Canon iR C2880i

[Lazuli]

I've got a Canon iR C2880i that is putting a row of little yellow dots across the page about 43mm apart. This seems to me to be caused by the PCR in the drum unit but before I replace this unit it would be nice to get other opinions.

Am I on the right track or does someone think there may be something else I should look at? Your input will be most welcome.

Regards
David