A couple of folks have changed the code to add a longer wait and the authors have it fixed in the git tree. But the fix hasn't been released yet. So you can compile the code yourself and test it or wait for the next release.
Sam
is it possible that this has the same reason:

a few days it has run with 7 Block erupter without Problems, then it has begun to error
it is the same hub as before, (I have changed nothing), then I tried another hub, another port, cgminer different versions, -> always errors
(Ubuntu 12.04)
TIA