[Alsa-user] Duplex & Surround sound on Turtle Beach Santa Cruz (cs46xx)

[Samuel Theobald]

Hi,

I'm trying to get my Turtle Beach Santa Cruz (cs46xx) to record 2 channels and playback 4 channels (front & rear) simultaneously with jack (using qjackctl to get jack going)

My sound card works fine in 2 channel capture, 2 channel playback using hw0.
The driver doesn't let me use 4 channels with hw0.

With the following .asoundrc I can get it to playback in 4 channels.
------------ .asoundrc --------------
ctl.quad {
    type hw
    card 0   
}

pcm.quad-setup {
        type multi

        slaves.a.pcm "hw:0,0"
        slaves.a.channels 2
        slaves.b.pcm "hw:0,1"
        slaves.b.channels 2

        bindings.0.slave a
        bindings.0.channel 0
        bindings.1.slave a
        bindings.1.channel 1
        bindings.2.slave b
        bindings.2.channel 0
        bindings.3.slave b
        bindings.3.channel 1
}

pcm.quad {
        type route
        slave.pcm "quad-setup"
        ttable.0.0 1
        ttable.1.1 1
        ttable.2.2 1
        ttable.3.3 1
}
---------------------------

trying to enable capture using (default), hw0 or hw0,0 causes the following error:
ALSA: Cannot open PCM device alsa_pcm for capture. Falling back to playback-only mode

I have also tried the surround40 plugin with associated code found on alsa.opensrc.org
-------- .asoundrc -----------
ctl.jack40 {
    type hw
    card 0
}

pcm.jack40 {
    # "asym" allows for different
    # handling of in/out devices
    type asym
    playback.pcm {
        # route for mmap workaround
        type route
        slave.pcm surround40
        ttable.0.0 1
        ttable.1.1 1
        ttable.2.2 1
        ttable.3.3 1
    }
    capture.pcm {
        # 2 channels only
        type hw
        card 0
    }
}
-----------------------

This works fine in playback only mode, but fails in duplex mode:

------------------------------
21:55:29.567 /usr/bin/jackd -R -dalsa -djack40 -r44100 -p128 -n2 -S -o4
21:55:29.582 JACK was started with PID=4350 (0x10fe).
jackd 0.100.1
Copyright 2001-2005 Paul Davis and others.
jackd comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
JACK compiled with System V SHM support.
loading driver ..
apparent rate = 44100
creating alsa driver ... jack40|jack40|128|2|44100|0|4|nomon|swmeter|-|16bit
configuring for 44100Hz, period = 128 frames, buffer = 2 periods
nperiods = 2 for capture
nperiods = 2 for playback
21:55:31.628 Server configuration saved to "/home/teppic/.jackdrc".
21:55:31.631 Statistics reset.
21:55:31.669 Client activated.
21:55:31.672 Audio connection change.
21:55:31.681 Audio connection graph change.
ALSA: poll time out, polled for 4352108 usecs
DRIVER NT: could not run driver cycle
jack main caught signal 12
21:55:34.237 Shutdown notification.
21:55:34.238 Client deactivated.
no message buffer overruns
21:55:34.241 JACK was stopped successfully.
zombified - calling shutdown handler
-----------------------------

Is multichannel playback and simultaneous capture supported, and if so, does anyone have a working .asoundrc file or other solution?
Is this a jack problem & something I need to ask the developers of jack?

Thanks for your time.

Sam Theobald