Hi Neglefil,
I assume you are running FAAH using BOINC 5.4.9 0r 5.4.11 on Windows. Go to your Device Profile and look at 'Leave applications in memory while preempted?' What does that say?

Also, look at the messages tab in the BOINC Manager. Is there anything unusual there?

Finally, how many hours does FAAH run at a time? It may not be reaching a check point. This last possibility is difficult to check in BOINC because it does not write a message when it checkpoints. The number of check points in a FAAH work unit is highly variable. A few work units have no check points, a larger number have only a few, but most checkpoint several times an hour. I have requested a change to show when a check point is written, since this can be a real puzzler.

Lawrence