Something is blocking audio controls?

Lately I noticed that something seems to be blocking various audio controls - mixer mostly. I can't access mixer window from taskbar, my keyboard volume knob doesn't work, mute too.

But - all the generated events are there, because when the problem goes away (usually in the range of 10-30 seconds), all the events that I generated (volume up/down, mute) are applied.

Any idea on what could that be, or how to debug it?

Straced kmix startup. And it looks like it was waitinf for some information from dbus - i see it sent and received some messages to fd=3 (which is earlier connected to /tmp/dbus-something), and then it waits 21 seconds!, and then it gets new message from dbus, message looks like:

27888 15:16:43.485816 recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"l\2\1\1\302\v\0\0,\0\0\0.\0\0\0\6\1s\0\6\0\0\0:1.102\0\0\5\1u\0\t\0\0\0\10\1g\0\1s\0\0\7\1s\0\5\0\0\0:1.44\0\0\0\275\v\0\0<!DOCTYPE node PUBLIC \"-//freedesktop//DTD D-BUS Object Introspection 1.0//EN\"\n\"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd\">\n<node>\n  <interface name=\"org.kde.KApplication\">\n    <method name=\"updateUserTimestamp\">\n      <arg name=\"time\" type=\"i\" direction=\"in\"/>\n    </method>\n    <method name=\"updateUserTimestamp\">\n    </method>\n    <method name=\"reparseConfiguration\">\n    </method>\n    <method name=\"quit\">\n    </method>\n  </interface>\n  <interface name=\"com.trolltech.Qt.QApplication\">\n    <property name=\"cursorFlashTime\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"doubleClickInterval\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"keyboardInputInterval\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"wheelScrollLines\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"globalStrut\" type=\"(ii)\" access=\"readwrite\">\n      <annotation name=\"com.trolltech.QtDBus.QtTypeName\" value=\"QSize\"/>\n    </property>\n    <property name=\"startDragTime\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"startDragDistance\" type=\"i\" access=\"readwrite\"/>\n    <property name=\"quitOnLastWindowClosed\" type=\"b\" access=\"readwrite\"/>\n    <property name=\"styleSheet\" type=\"s\" access=\"readwrite\"/>\n    <property name=\"autoSipEnabled\" type=\"b\" access=\"readwrite\"/>\n  </interface>\n  <interface name=\"com.trolltech.Qt.QCoreApplication\">\n    <property name=\"applicationName\" type=\"s\" access=\"readwrite\"/>\n    <property name=\"applicationVersion\" type=\"s\" access=\"readwrite\"/>\n    <property name=\"organizationName\" type=\"s\" access=\"readwrite\"/>\n    <property name=\"organizationDomain\" type=\"s\" access=\"readwrite\"/>\n  </interface>\n  <interface name=\"org.kde.KUniqueApplication\">\n    <method name=\"newInstance\">\n      <arg type=\"i\" direction=\"out\"/>\n      <arg name=\"asn_id\" type=\"ay\" direction=\"in\"/>\n      <arg name=\"args\" type=\"ay\" direction=\"in\"/>\n    </method>\n    <method name=\"newInstance\">\n      <arg type=\"i\" direction=\"out\"/>\n      <arg name=\"asn_id\" type=\"ay\" dir", 2048}], msg_controllen=0, msg_flags=MSG_CMSG_CLOEXEC}, MSG_CMSG_CLOEXEC) = 2048 <0.000008>

It contains string "introspection" - no idea what it is about, but perhaps it could be related?

I am very willing to do additional tests/straces/whatever to solve the problem, so if you have any ideas - please speak up.

user7385

Posted 2011-03-21T16:24:56.727

Reputation:

What Linux Distro and Audio Card do you have? – Riguez – 2011-03-24T13:57:46.713

It's kubuntu maverick. as for sound card - lspci shows: 00:1b.0 Audio device: Intel Corporation 82801JI (ICH10 Family) HD Audio Controller – None – 2011-03-24T16:48:38.950

Answers

Not an answer but lets me better format my suggestions than commenting.

Get your hands on some .wav files not sure what aplay supports natively but no point in trying to get it to support something like mp3 if it doesn't already.

Try to eliminate as my conflicting processes as possible by typing this at the command prompt.

sudo init 3 ...this should drop you to the command-line only you can eliminate even more by entering single user mode sudo init 1 but it might eliminate to much not sure.
Log in if not already and type alsamixer if its not found try sudo apt-get install alsa-utils first. Alsamixer will allow you to manipulate the volume with your arrow keys in the interface that it launches.
Hit ctrl+alt+f1 this should bring you to a fresh command prompt login again.
Execute aplay /path/to/sound.wav the file should start playing.
Hit ctrl+alt+f7 to get back to the alsamixer if it is a blank prompt flip through them to find which one it is ctrl+alt+f2... etc etc.
Start adjusting the volume to see if there is a delay.

sudo init 5 to get back your GUI

Riguez

Posted 2011-03-21T16:24:56.727

Reputation: 3 594

alsamixer works fine even in konsole/kde. i suspect the dbus, but have no idea what it could be. – None – 2011-03-24T17:58:28.343

If the audio system works fine with alsamixer. Installing the proper drivers for your keyboard should fix that issue. Now we need to figure out what is wrong with the GUI audio mixer I have not used kubuntu so I dont know the name of it but if you could right click on the mixer and click about if it exists.. you can find out what the name of it is you could try uninstalling it and its related files and reinstalling it to see if something was broken.... – Riguez – 2011-03-24T19:45:18.443

after doing a search looks like it might be kmix.. an alternative to this is kalsamixer http://kalsamix.sourceforge.net/shots.php

– Riguez – 2011-03-24T19:48:39.377

screensaver is also slow to finish. kmix is just one of applications that's easy to test. as for keyboard - keyboard works just fine. and the slowdown happens also when I click on icons (like the icon for kmix), or when closing screensaver. – None – 2011-03-25T08:12:33.130

gahhhh why are you posting that now lol – Riguez – 2011-03-25T10:58:17.513

What are your computers specs... and did this start recently or has it always been like this? Did you try a different distro using a LiveCD and it was the same? You might need to tone it down if it is just your computer not being able to handle it maybe try crunchbang or if you are like me use archlinux and build it up with openbox and tweak it exactly like you like it. – Riguez – 2011-03-25T11:06:07.707

https://help.ubuntu.com/community/Installation/SystemRequirements – Riguez – 2011-03-25T11:10:22.510

you should also sudo apt-get install htop and run it so you can get a better idea of how your system is doing. – Riguez – 2011-03-25T11:11:11.807

I have htop. System is not loaded. It's 12GB, i7 920, with wd velociraptor drives (/ on one disk, and /home on another). have yet to see it with load over 2. – None – 2011-03-25T23:28:35.967

Did you try to run the Kubuntu/Ubuntu LiveCD to see if the issue is the same in a clean environment? – Riguez – 2011-03-26T00:22:36.780

No. Reason is very simple - I remember that after install everything worked perfectly for some time, it just got worse afterwards. And (although it's less of an issue) I don't have any installation/live cd. – None – 2011-03-26T17:15:58.683

Had to ask you didn't state your question very clear saying "lately you noticed" something kinda implies it could have been there the entire time as opposed to it "worked perfectly" and then broke. – Riguez – 2011-03-26T17:26:39.657

try running "sudo apt-get update" and then "sudo apt-get install --fix-broken" – Riguez – 2011-03-26T17:27:01.667

system is up to date, nothing broken. installation of updates happens at least twice a week. – None – 2011-03-28T10:33:30.810

try this and reboot "sudo adduser your_username audio" – Riguez – 2011-03-29T13:13:30.380

here is a guide for normal ubuntu but should work for kubuntu http://www.howtogeek.com/howto/10964/how-to-fix-sound-issues-in-ubuntu-9.10/ ... I am thinking that an update broke your audio it happens :\

– Riguez – 2011-03-29T13:22:48.330

another thing to try is kill off pulse and use just alsa... "sudo apt-get remove pulseaudio-utils pulseaudio" & "pkill kmix && sudo alsa force-reload && kmix" then under "System Settings -> Multimedia" change your settings to ALSA/Your Audio card – Riguez – 2011-03-29T13:29:49.540

I need pulse because sometimes I use two soundcards - normal built in, and second, on usb - interface for wireless headphones. As for text on howtogeek - I don't have any of the problems they mention, so it's hard to judge whether it can be related. will try anyway. as for adding user to group. will do so, but reboot will take some time. – None – 2011-03-29T16:10:40.743

tested. adding myself to audio group didn't help. – None – 2011-03-30T09:23:56.497

:\ personally don't know what to tell you short of reinstalling and monitoring your updating... because it was working and then it wasn't after what I am assuming was many updates. This tells me one of them broke it or something else you installed separately broke it. If I were you I would not have them automatically install read on them first, It could have been an update to pulse itself seeing as it is always issues at least from what I have seen. – Riguez – 2011-03-30T13:47:35.187

sure, i understand. well - i still have no idea what it could be :( reinstallation is technically possible, but i'd prefer to avoid it. – None – 2011-03-30T19:49:11.430

You can get rid of kmix entirely and use shorcuts instead:

amixer -c 0 set Master 3- unmute
amixer -c 0 set Master 3+ unmute
amixer -c 0 set PCM 3- unmute
amixer -c 0 set PCM 3+ unmute

The first two will raise/lower the Master volume, the last two will do the same for PCM channel.

I have them mapped to Win+Up, Win-Down, and Ctr+Win+Up, Ctr+Win+Down accordingly. No more mousing around.

ccpizza

Posted 2011-03-21T16:24:56.727

Reputation: 5 372

Well, sure, I know. I can also bind it to keyboard shortcuts. But I'm much more interested in source of the problem, and proper fix of it, rather than workaround. – None – 2011-03-28T22:04:55.440