Adobe Acrobat Distiller Hangup

Running Acrobat 9.5.5 on a 2008R2 Enterprise 64 bit Terminal Server. Acrobat 9 (and consequently Distiller) is a 32 bit app.

Starting about a month ago we started getting seemingly random complaints from users unable to make PDF files via the "Adobe PDF" printer. Everything would appear to go normally, but there would be nothing created. When i would subsequently log on as Administrator to that server, Windows would tell me that there were background applications I needed to see (similar to the sort of prompt you get from UAC) and when I would view them there would be all of their PDF files. It was as if the Distiller was handing off the completed PDF jobs correctly, but it was handing them off to Administrator instead of the user that created the job.

Now we're getting (again, seemingly randomly, can't narrow to a specific app, user, circumstance, etc.) the "Adobe PDF" printer failing to distill those jobs in the first place. When I pull up the queue, sure enough there will be job #1 sitting at the top as "ERROR" with others behind it. Pausing the printer, killing job #1, restarting the spooler, and un-pausing the printer will usually take care of it. Sometimes I have to kill all the jobs.

I did notice that the acrodist.exe process is running as "SYSTEM" where as on the other terminal server it runs as the user that originated the job. The other terminal server is 32-bit, though, so I don't know if Windows is working some sort of middleman voodoo on the 64-bit server to get it to talk to the 32-bit print driver, and that is what is causing it to run as SYSTEM. The original problem of the files showing up in the background of the Administrator account made me suspicious of possible account mis-matching, though.

Nothing in the Event logs when this happens. It seemed to start after an Acrobat update 9.3->9.5

Thanks in advance for any help.