10.04 - volume stuck on mute.

[earthpigg]

hi,

problem: starting yesterday, around update time, sound ceased working. after restarting, sound output is still not working. the applet is stuck on 'mute all', and is greyed out.

opening the sound preferences from the applet, and going to the 'output' tab, i see that the only device for sound output available to me is 'dummy output'. screenshot attached, to clarify.

rhythmbox, and other things that play sound, don't object to me hitting the 'play' button... time ticks as if they where playing sound, but it is still muted.

running alsamixer from the command line...

[chris: ~]$ alsamixer
cannot open mixer: No such file or directory

i am certain alsamixer is installed.

running gnome-alsamixer returns an empty window with the usual menu items at the top. selecting anything, however, returns this:

[chris: ~]$ gnome-alsamixer

(it opens, then i click on a menu item...)

(gnome-alsamixer:2353): GLib-GObject-CRITICAL **: g_type_instance_get_private: assertion `instance != NULL && instance->g_class != NULL' failed
Segmentation fault

ive clicked through all the obvious tabs and whatnot in the sound preferences.

possible cause:

-update is the most likely one, of course.
-DEFCON, the game.

something else interesting... yesterday, after updating, i kept using my computer even though it told me to restart. i was in the middle of playing DEFCON, and kept playing. the defcon sound kept working, but all other sound died. "all well", i figured, "im sure the wonkyness will sort itself out next time i restart".

no dice.

DEFCON isn't 'installed' in the traditional sense, you just extract it and run as user (not root). it was downloaded directly from the vendor's website. i don't see how this could cause breakage.

anyways, advice or ideas?


EDIT:

update - ok, so it definately WAS something DEFCON did while running with normal user privileges. when i logged into another account, sound worked perfectly. logging back into "chris", it no longer works again. anyone know the dotfile or whatever that i can simply delete to restore this username's sound preferences to default?

EDIT2:

ok, it's definately something with this specific user. running "sudo alsamixer" works fine, but just "alsamixer" does nada. my intuition tells me it's something i should be able to fix without being root, since all users work except this one.

EDIT3:

logging into a different username, i can go to the sound preferences applet -> hardware tab -> see the 'internal audio' device listed, along with several profiles and whatnot. logged in as my main (broken) user, the area below "Choose a device to configure:" is completely blank, and no profiles are listed.

EDIT4:

here is the contents of the shell script that runs DEFCON. pay attention at the end.

#!/bin/sh

# Function to find the real directory a program resides in.
# Feb. 17, 2000 - Sam Lantinga, Loki Entertainment Software
FindPath()
{
    fullpath="`echo $1 | grep /`"
    if [ "$fullpath" = "" ]; then
        oIFS="$IFS"
        IFS=:
        for path in $PATH
        do if [ -x "$path/$1" ]; then
            if [ "$path" = "" ]; then
                path="."
            fi
            fullpath="$path/$1"
            break
        fi
    done
    IFS="$oIFS"
    fi
    if [ "$fullpath" = "" ]; then
        fullpath="$1"
    fi

    # Is the sed/ls magic portable?
    if [ -L "$fullpath" ]; then
        #fullpath="`ls -l "$fullpath" | awk '{print $11}'`"
        fullpath=`ls -l "$fullpath" |sed -e 's/.* -> //' |sed -e 's/\*//'`
    fi
    dirname $fullpath
}


here="`FindPath $0`"

if [ ! -f "$here/lib/sounds.dat" ] ; then 
	echo "$0: Fatal error: missing sound data files (sounds.dat) in $here/lib"
	echo ""
	echo "Maybe you are missing sounds.dat (You need to download it"
	echo "separately from http://download.introversion.co.uk/defcon/sounds.dat"
	echo "and install it in the $here/lib"
	exit 1
fi
export LD_LIBRARY_PATH="$here/lib:$LD_LIBRARY_PATH"
$here/lib/defcon.bin.x86 "$@"

[earthpigg]

Solved.

posting what fixed it, in case others come across this.

I have no idea what caused this problem, but re-installing ubuntu-desktop with the dependencies i've removed over time, and restarting the computer, fixed it.

here are the packages that came with "sudo apt-get install ubuntu-desktop", from /var/log/apt/history.log

Start-Date: 2010-06-14  13:41:04
Install: hplip (3.10.2-2ubuntu2), ubuntu-desktop (1.197), foomatic-db-engine (4.0.4-0ubuntu1), foomatic-db (20100216-0ubuntu3), hplip-data (3.10.2-2ubuntu2)
End-Date: 2010-06-14  13:41:54