Audio config

Install jackd2 from /root/jackd2, which is a jackd2 compiled without dbus (--dbus removed from debian/rules in the debian source package). Make sure to enable rtprio and memlock permissions, the jackd installer on debian asks for this.

Make a new file /root/jackd_start, chmod to 755 and put this in it:

#!/bin/bash

#make sure jackd and bobdsp are terminated when this script ends
cleanup()
{
  killall jackd
  killall bobdsp
  exit 0
}
trap cleanup SIGINT
trap cleanup SIGTERM

#JACK_PROMISCUOUS_SERVER is exported here and in /etc/environment
#this tells jackd and libjack to use /dev/shm/jack instead of /dev/shm/jack-<uid>
#and to set the permissions to 777, however umask needs to be set to 0 first
export JACK_PROMISCUOUS_SERVER=""

#allow rtprio and mem locking
ulimit -l unlimited
ulimit -r 95

#start bobdsp
su -l bitlair -c "cd /home/bitlair/bobdsp; ./build/bobdsp -f -d"

#start jackd with -l passed to su to make the environment a login shell, restart when it dies
#jackd needs to run as root, probably because it needs to send signals to its clients
while [ 1 ]
do
  su -l -c "mkdir ~/.jackd; umask 0; jackd -R -d alsa -d jack51 -r 48000 -p 1024 -n 2 -i 2 -o 6 2>&1 | tee ~/.jackd/jackd.log" || true
  sleep 1
done

Put this in /etc/rc.local

/root/jackd_start&

At the top of /etc/init.d/mpd change

#!/bin/sh

to

#!/bin/bash

Then change

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

into

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

#allow rtprio and mem locking
ulimit -l unlimited
ulimit -r 95

And

user				"mpd"

into

user				"bitlair"

Then run as root:

dpkg-statoverride --remove /var/run/mpd
dpkg-statoverride --add bitlair audio 755 /var/run/mpd

chown -R bitlair:audio /var/lib/mpd
chown -R bitlair:audio /var/run/mpd
chown -R bitlair:audio /var/log/mpd

Use this /etc/asound.conf file

pcm.!default {
    type plug
    slave { pcm "jack" }
}

pcm.jack {
    type jack
    playback_ports {
        0 system:playback_1
        1 system:playback_2
        2 system:playback_3
        3 system:playback_4
        4 system:playback_5
        5 system:playback_6
    }
    capture_ports {
        0 system:capture_1
        1 system:capture_2
    }
}

ctl.mixer0 {
    type hw
    card 0
}

ctl.jack51 {
    type hw
    #card 0
    card Audigy
}

pcm.jack51 {
    # "asym" allows for different
    # handling of in/out devices
    type asym
    playback.pcm {
         # route for mmap workaround
         type plug
         slave.pcm "surround51:CARD=Audigy"
         #slave.pcm "surround51"
         slave.channels 6
         route_policy duplicate
    }
    capture.pcm {
        # 2 channels only
        type hw
        #card 0
        card Audigy
    }
}

In /etc/mpd.conf comment the current audio output, and use this instead:

audio_output {       
       type    "jack"       
       name    "mpd"     
}