You may want to check whether it is JACK enabled. I've only ever used
the debian derivative Ubuntu, and I'm not sure whether they also have
that ridiculous "cannot link to apps in different repos" rule that
prevented JACK support for some apps.
I just checked; I installed mine from the Debian Multimedia repo, not
the vanilla Debian. I'm also using the Rivendell repos for Jack, it's a
very good place to find a very stable, reliable, repo-aware Jackd.
Please clarify if you mean debian-multimedia.org (unofficial, not
supported by debian) or packages from pkg-multimedia-maintainers.
Also, the official multimedia team in debian is trying hard to take care
of things and has had a recent surge of activity. Please, please, report
bugs to the BTS if things break using the official packages.
I am using the attached /etc/apt/sources.list. Synaptic properties for
my jackd package are:
Debian Multimedia Maintainers
which is quite odd considering that with the Debian Multimedia repo
alone, I did not have access to this Jack package (0.118+svn3796-1).
Also and by the way, Audacity is now working for me via either Pulse or
Jack (ldconfig and reboot got Pulse working), although Jack works
beautifully whereas Pulse seems to cut in and out just a bit.