On a random basis, AP will submit a payables run (t-code F110) and some checks will not print. When this occurs it usually involves one or two entire company codes, out of several which are included in the proposal. It does not always happen, and it does not always involve the same company code(s).
If we rerun the check print portion of the proposal (cancel and reprint checks using program RFFOUS_C), the missing checks print just fine. So I don't think there's anything wrong with the print program or the variant.
It seems to be at the point where SAP hands off the print spool file to the print server, but as I say it's so random there's no clear clue. I wasn't sure if Financials is the correct forum for this problem.

