module-jackdbus-detect in PulseAudio

David Henningsson david.henningsson at
Fri Dec 10 08:36:16 GMT 2010

Hello Ubuntu Studio and Audio developers,

A week or two ago I wrote a new PulseAudio module that detects the 
presence of JACK server, and adds a sources and a sink when JACK is 
started. It is now being shipped in Natty since yesterday [1].

This version uses JACK's dbus interface to detect server being started 
or stopped, i e /usr/bin/jackdbus instead of /usr/bin/jackd.
If you use qjackctl to control the server, make sure that you check the 
checkbox "Enable D-Bus interface" under Setup -> Misc.

* Anybody against me changing the default of qjackctl in Natty to have 
this checkbox checked?

The other open question, where I'm not sure, is about the default, and 
I'd like your opinion on the matter. We have these options:

1) We start it by default via the startup script.

2) We do not start automatically when PulseAudio starts, but add a 
checkbox to the paprefs application that optionally starts this module.

For both versions, there is this question as well:

a) We have autoconnect=true, which means that the PA Jack sink will 
connect to the "system"/soundcard sink of JACK

b) We have autoconnect=false, which means there will be a PA Jack sink 
but you'll have to connect it to something yourself.

(The same thing applies to the PA Jack Source, of course.)

David Henningsson, Canonical Ltd.

[1] Perhaps one should wait a day or two before upgrading though, see

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