Table of Contents

Pulse Audio

Some nice graphical tools:

sudo apt-get install paprefs pavucontrol
killall pulseaudio
pulseudio -v
pacmd list-sinks
pacmd list-cards

disable autospawn

/etc/pulse/client.conf
; autospawn = yes
pulseaudio --kill
pulseaudio -v

mpd player

audio_output {
        type                    "pulse"
        name                    "MPD PulseAudio Output"
        server                  "127.0.0.1"
}
/etc/pulse/default.pa
load-module module-native-protocol-tcp auth-ip-acl=127.0.0.1

no alsa MIC input

Check for existence of arecord process. It can be used to sample noise and feed a kernel entropy (package randomsound)

https://bugs.launchpad.net/ubuntu/+source/randomsound/+bug/590780

randomsound has to be started AFTER pulse audio. It is hard to achieve because pulse is started as from user graphical session. As workaround it is nice to disable or remove rendomsound package.

Simultaneous on HDMI and Analog

Run paprefs, go to last tab “Simultaneous Output” and enable feature. This will add new device for both HDMI and Analog output and set it as default one.

No sound

As as normal user try to start

pulseaudio --check

command:

E: [pulseaudio] core-util.c: Failed to create secure directory (/run/user/1000/pulse): Permission denied
ls -l /run/user/1000/

shows that pulse dir is owned by root (Probably pusleaudio was spawned when user switch to root using su or sudo)

rm -r /run/user/1000/pulse

No sound with NVidia graphic card

Only USB camera and NVIDIA HDMI outputs are visible.

pacmd list-cards
 
2 card(s) available.
    index: 0
	name: <alsa_card.pci-0000_01_00.1>
	driver: <module-alsa-card.c>
	owner module: 6
	properties:
		alsa.card = "1"
                alsa.card_name = "HDA NVidia"
 
index: 1
	name: <alsa_card.usb-046d_0825_38C54AA0-02-U0x46d0x825>
	driver: <module-alsa-card.c>
	owner module: 7
	properties:
		alsa.card = "2"
		alsa.card_name = "USB Device 0x46d:0x825"
                device.product.name = "Webcam C270"
$ aplay -l 
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC892 Analog [ALC892 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: ALC892 Digital [ALC892 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 7: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 8: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 9: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Reloeading UDEV detecection module doesn't help.

pacmd unload-module module-udev-detect && pacmd load-module module-udev-detect

After this I got doubled USB camera and NVIDIA output :(

### Load audio drivers statically
### (it's probably better to not load these drivers manually, but instead
### use module-udev-detect -- see below -- for doing this automatically)
#load-module module-alsa-sink
#load-module module-alsa-source device=hw:1,0
#load-module module-oss device="/dev/dsp" sink_name=output source_name=input
#load-module module-oss-mmap device="/dev/dsp" sink_name=output source_name=input
#load-module module-null-sink
#load-module module-pipe-sink
...
load-module module-udev-detect
...

pusleaudio -v shows lots of

I: [pulseaudio] alsa-util.c: Error opening PCM device front:1: No such file or directory
I: [pulseaudio] (alsa-lib)pcm_hw.c: open '/dev/snd/pcmC1D0c' failed (-2)
I: [pulseaudio] alsa-util.c: Error opening PCM device hw:1: No such file or directory
killall pulseaudio
rm -r ~/.config/pulse/*
pulseaudio -v

load-module module-alsa-sink device=hdmi:0 load-module module-combine-sink sink_name=combined set-default-sink combined