I had noticed over the last few weeks that my rate was going down and that my "Active processors in the last 7 days" was reporting below the actual number of processors which I have crunching. I checked out 2 of my Xserves and noticed that several of the files in the working directory had not been modified for at least 2 weeks.
I deleted those few files (FAHlog.txt, queue, unitinfo.txt, and work/) and restarted fah5 and those files showed they had been modified the next time I listed the directory. Now, sure enough, my rate is back up a few hundred points. Anyone seen this type of behavior?