From the ALSA wiki
I found this hardware to work well with alsa under many default debian-type installations and with many apps. I've found it has nice clean audio when everything is well-configured.
I've successfully used this hardware with alsa and a default-userland installation of jack. I kept getting lots of xruns when I connected a client, along with this error
Subgraph starting at ecasound timed out (subgraph_wait=..., status=0, state=running)
and something about zombifying and then exit? I played with the buffers to no avail. _Finally_ I tried increasing jackd's timeout (with -t int_usecs), which defaults to 500usec, to a very large number. It's worked like butter ever since.
Retrieved from "http://alsa.opensrc.org/Griffin_iMic"