[Jack-Devel] jack and ALSA driver

Hello!

I am trying to use a zoom h4n with JACK. The device appears to be supported
by ALSA (though it is not listed in the device matrix), as I can play and
record audio through it using the default ubuntu sound config tool, and I
can play audio through it using aplay at the same time as successfully
recording using arecord.

However, when I try to use the device with JACK, at startup I get

...

Wed Nov 23 13:32:38 2011: Starting jack server...

Wed Nov 23 13:32:38 2011: JACK server starting in realtime mode with
priority 68

Wed Nov 23 13:32:38 2011: control device hw:1

Wed Nov 23 13:32:38 2011: control device hw:1

Wed Nov 23 13:32:38 2011: Acquired audio card Audio1

Wed Nov 23 13:32:38 2011: creating alsa driver ...
hw:1|hw:1|512|3|44100|0|0|nomon|swmeter|-|16bit

Wed Nov 23 13:32:38 2011: control device hw:1

Wed Nov 23 13:32:38 2011: configuring for 44100Hz, period = 512 frames
(11.6 ms), buffer = 3 periods

Wed Nov 23 13:32:38 2011: ALSA: final selected sample format for capture:
16bit little-endian

Wed Nov 23 13:32:38 2011: ALSA: use 3 periods for capture

Wed Nov 23 13:32:38 2011: ALSA: final selected sample format for playback:
16bit little-endian

Wed Nov 23 13:32:38 2011: ALSA: use 3 periods for playback

Wed Nov 23 13:32:38 2011: [1m[31mERROR: ALSA: could not start playback
(Broken pipe)[0m

Wed Nov 23 13:32:38 2011: [1m[31mERROR: Cannot start driver[0m

Wed Nov 23 13:32:38 2011: [1m[31mERROR: JackServer::Start() failed with
-1[0m

Wed Nov 23 13:32:38 2011: [1m[31mERROR: Failed to start server[0m

Wed Nov 23 13:32:38 2011: control device hw:1

Wed Nov 23 13:32:38 2011: Released audio card Audio1

Wed Nov 23 13:32:38 2011: control device hw:1

13:32:52.327 Could not connect to JACK server as client. - Overall
operation failed. - Unable to connect to server. Please check the messages
window for more info.

...


If I configure the device for capture only using the command line
jack_control program, I can start the jack server.


Is there a way I can get more information from the ALSA driver, when it is
used by jack? Is there a way I can find out more details about what is
causing the 'Broken pipe'. The verbose option in jack only gives me more
messages from jack, and not any more from ALSA. Any tips for trouble
shooting the problem, or achieving duplex operation? Any other suggestions
are welcome too!


Thanks!

Tim

1322016065.29348_0.ltw:2,a <CAHb6uwfXm1JqC-bkd40UWo+35ZqycMnkwLhP549eSESmQUVetw at mail dot gmail dot com>