NDPS problems again

We're getting this bug:
NDPSGW-3.01g-NDPS OPERATION ERROR(prhh154-2): The 208 operation to the NDPSM failed.

If needed, the Error Codes explanations in the online System Messages documentat
ion may provide additional information about the following return codes.
Error code: -704 (0xFFFFFD40)
We've had it before. This is one of three ways that the printer-agents in our pools can go unresponsive. This is also the first time I've caught one of them at this. The -704 error is probably an NDPS/NDPSM/NDPSGW error and not a DS error, much as they share the same error codes. Not 100% on that one. I'll see what I can dig out of developer docs.