Printing -header problem

When I printed out my grid the header didn't print out correctly. It was almost like a white box is 'laid' over the header text. Everything else printed out perfectly though.

Any ideas why? It may be just firefox?

TIA

this box has, what it seems, three sets of 2 very very small arrows in it, one facing up, one facing down.

Has anybody else experienced this problem when printing...maybe with FF?

If you can try and replicate it here are the circumstances

landscape view, background on, FF 1.5.0.1

Alex, Is it a result of the trial version? Have you ever seen this before?