Ricoh SG 3110DN - Print Quality Suddenly Terrible?

[magsachu]

Have you tried using a piece of paper from a newly opened pack, to see if damp paper is the problem?

The coating on sublimation paper soaks up moisture much quicker than other papers. Now that the weather is slightly warmer and damper any reduction in your heating could be enough for opened packs to suck up any moisture in the air.
I always store my opened packs in a ziplock bag, with one of those poundshop 'dehumidifier' silicon packs in the bag.

I've got some new paper arriving today which I will try and report back. Thanks for the tip about storing it in ziplock bags, I will do that going forward!