Audio issues appear in 10.04 - crackling and speed problems

[silentmonkey]

I did a reformat/install of Kubuntu 10.04 on my ASUS f3jr laptop once the final version was released and, mostly, I like it. I've been a long time user of Kubuntu on this same laptop, but since installing 10.04 I'm having sound issues for the first time. This may or may not be related to performance issues I'm also experiencing - for the first time ever, it sometimes takes a second or five to switch windows, open the save dialogue in Openoffice.org, etc.

I have a list of all the commands I have used since installing. The only thing out of the ordinary was that I installed UFO:AI for the first time to try it out. I got some missing dependencies error and read somewhere that I may need the following commands to get it working:

sudo apt-get install libsdl-ttf2.0-0
sudo apt-get install libsdl-mixer1.2
sudo apt-get install libcurl4-gnutls-dev

I could finally get the game running, but it was noticeably slow and the sound was, for lack of a better description, 'crackling' or 'choppy' or 'popping'. It's as though the system was having trouble performing under a lot of strain, so everything, including the sound, was coming out slower than it should, and would pause for a few seconds occasionally for the system to catch up. Altering sound or video settings made no difference at all.

I thought it was just the game, but I hadn't actually tried using sound elsewhere yet, as I hadn't yet transferred my music. I currently have Amarok playing in the background and everything sounds normal . . . but when my desktop background changes (set to every two minutes or something) I hear the same crackling in the audio and the system slows down for a second or two while the transition happens. Because one of the first configuration tasks I do when I install Kubuntu is turn off the login/logout audio alerts, I can not confirm whether or not this has been an issue from the beginning. (Though I seem to recall occasional performance strain before installing UFO:AI.)

SMplayer has displayed similar issues, too. Occasionally 'crackling' for a second or two while the video is jumpy. In hindsight, this happened about as regularly as my desktop changes, so that's probably the direct cause of that - but it would be good for it not to happen at all! The solution of 'just not having my desktop change' would only be a Band-AidTM fix for something more severe. Besides, this happens at other times, too, such as scrolling up and down in Firefox - which I sometimes do just for the fun of it!

Other multimedia related commands I have run are:

cd /etc/apt/sources.list.d/
sudo wget http://www.medibuntu.org/sources.list.d/$(lsb_release -cs).list
sudo apt-get -q update
sudo apt-get --yes -q --allow-unauthenticated install medibuntu-keyring
sudo apt-get -q update
sudo aptitude install libdvdcss2
sudo aptitude install w32codecs

And I have installed kubuntu-restricted-extras.

I have read elsewhere (http://kubuntuforums.net/forums/inde...opic=3104057.0) that such things may be a result of PulseAudio being annoying, but that does not seem to be installed on 10.04 by default, and the "sudo apt-get remove --purge pulseaudio" command informs me that it does not exist. In multimedia settings, my sound card is right at the top like it should be, for all sections.

According to lspci, I have an "Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02)".

Has anyone encountered similar audio or performance issues with 10.04? Or are there any suggestions as to how I can try to repair it? I can supply more details if you can think of something which could be relevant.

Thanks for reading!

ETA: To pre-empt the obvious suggestion, I just tried disabling compositing and can report that it makes no difference.

ETA2: I seem to have fixed it. Assuming I may have an issue somewhere because of the three commands I entered in order to get UFO:AI working, I got rid of them thusly:

sudo apt-get remove libsdl-ttf2.0-0
sudo apt-get remove libsdl-mixer1.2
sudo apt-get remove libcurl4-gnutls-dev
sudo apt-get autoremove

The problem was still present until I restarted. Now, with admittedly very minimal playing around, everything seemed to be working alright with audio. UFO:AI now didn't work, and I got the following message like I did originally:

./ufo: error while loading shared libraries: libSDL_ttf-2.0.so.0: cannot open shared object file: No such file or directory

I reinstalled libsdl-ttf2.0-0 and then I got the other message again:

./ufo: error while loading shared libraries: libSDL_mixer-1.2.so.0: cannot open shared object file: No such file or directory

I reinstalled libsdl-mixer1.2 and the game finally worked. Appears libcurl4-gnutls-dev is not required - no idea why I was instructed to install it. The game is still a little 'crackly', though not as bad as it previously was, and I'm not experiencing any crackling during Amarok playback, either, so that's a plus!

I'll update later if I ever work out how to run UFO:AI with smooth audio playback. Until then, I'll mark this post as SOLVED.

ETA3: Ok, so after a few minutes the sound issue returned. Perhaps these three commands have nothing to do with my issue. I have no idea why it wasn't present for the first few minutes of the system being up. I have removed '[SOLVED]' from the post title.

I have disabled Nepomuk Semantic Desktop and Strigi Desktop File Indexer, which seem to have some relation to my slow system. Going for a restart to see if this fixes it.

[oshunluvr]

Re: Audio issues appear in 10.04 - crackling and speed problems

Hate to point out the obvious - but I've found having kmix volume at 100% causes crackling in my speakers even though the volume knob on the speakers is reduced.

[silentmonkey]

Re: Audio issues appear in 10.04 - crackling and speed problems

. . . I've found having kmix volume at 100% causes crackling in my speakers . . .

Do you experience this constantly, or is it only intermittent? I do have kmix at 100% but I only have crackling issues occasionally, and only when my computer is actively doing something with video like Firefox scrolling or desktop wallpaper changing or playing one specific game.

I've also not changed my hardware at all since using previous versions of Kubuntu without sound issues.

I decided to actually test out your suggestion rather than assume it's a different issue. Putting both my 'PCM' and 'Master' channels at ~75% made no difference to the crackling.

Thanks for the reply, though!

It appears I may be the only one with this issue, judging from the lack of responses. I'll have a play around with things one day and update this post once I'm not working on a major assignment.

[oshunluvr]

Re: Audio issues appear in 10.04 - crackling and speed problems

More likely you're not the only one.

Do some web searching on your audio card and alsa.

There may be some options you can put in /etc/modprobe.d/alsa-base.conf that may ix or lessen your issue.

Keep working on it!

[Cresho]

Re: Audio issues appear in 10.04 - crackling and speed problems

pcm volume reduce to 80%