Sound problems

[Wedge_]

Sound problems

[Wedge_]

I've tried a few different distros with two different soundcards now (an Aureal Vortex 2 and a Turtle Beach Santa Cruz) and have run into the same problem every time. I can hear sounds no problem, but when I play MP3's, the sound breaks up very noticeably at the louder and lower parts of each song. It's also noticeable in Q3, but not so much when watching videos and DVD's. I've tried screwing around with every sound setting I can find, which isn't saying much , I've tried using the commerical OSS drivers, I've tried the ALSA drivers, which produced the same kind of noise, and now seem to cause lockups every time I try and use them. This is really, really annoying me Does anyone have any suggestions? The card I'm currently using is the Santa Cruz, and it works perfectly in Windows.

[gloval]

On the hardware side you could be running hard drives in PIO mode not DMA (hdparm -d1 /dev/hd...). The
problem sounds like clipping.  I presume the mp3 does not sound as bad in windows, there rubbish encoders
out there.

Another possibility is a BIOS setting,  I have one on mine Super Bypass mode [enabled/disabled], supposedly
for optimisations.  however when it is disabled any sound appears to be going through an echo chamber.  Your
windows drivers could be say re-enabling the option. You have to watch these motherboard people at times.

karl.

[Wedge_]

Changing between PIO and DMA doesn't seem to affect it. The MP3's sound fine in Windows, that definitely isn't the problem. I'll take a look at my BIOS manual and see if I can find anything there.

[gloval]

Are you sharing interrupts between the audio device and anything else, check /proc/pci or /proc/interrupts.  Is PNP OS
enabled in the BIOS.

karl.

[Wedge_]

I had PnP OS turned off in the BIOS, but the same thing happens with it turned on. I checked my mobo manual, and it says that the PCI slot I'm using for the soundcard shares an IRQ with the USB controller, and proc/pci and proc/interrupts say the same thing. I'm using a USB mouse, so I'll move the soundcard to another slot and see what happens.

[gloval]

It's best to disable the PNP OS option it just causes problems.  What are you using for playing sound
mpg123, xmms ??  if so what version of the software are you running.  uname -r for kernel.

karl.

[Wedge_]

Yeah I usually have PnP OS turned off. I tried switching the soundcard to another PCI slot, but it still seems to be sharing it's IRQ with the USB controller. Is there something else I need to do that could force it to use another IRQ? This is what /proc/interrupts gives:
          CPU0
 0:      60192          XT-PIC  timer
 1:       2326          XT-PIC  keyboard
 2:          0          XT-PIC  cascade
 4:     112926          XT-PIC  serial
 8:          1          XT-PIC  rtc
10:     198002          XT-PIC  ide2
11:      48604          XT-PIC  nvidia
12:      26976          XT-PIC  usb-uhci, cs46xx
14:          5          XT-PIC  ide0
15:         30          XT-PIC  ide1
NMI:          0
LOC:          0
ERR:          0
MIS:          0

I'm still pretty new to Linux, so I'm not so sure about stuff like this. I'm using Redhat 7.3 currently, with the 2.4.18-3 kernel that it comes with. I'm using xmms 1.2.7 for playing MP3's, but like I said, the MP3's are just where it's most noticeable. I can also hear the same thing playing Q3, and with a couple of other games.

[gloval]

Is it a different IRQ,  the two slots maybe hardwired to the same IRQ.  Not sure if Q3 use MP3 for audio some are
moving over to vorbis these days.  Try playing normal WAV files as well.   Can you make sure it isn't clipping, turn
down the mixer volume, some audio devices have mixers which fall apart around 80% and your windows drivers
may account for that.

karl.

[Wedge_]

If they are using the same IRQ, it's not mentioned in the manual. I'll try another slot and see what happens. I tried playing some sounds with the mixer volume turned down to around 50%, but it's still happening. I also converted a few MP3's to wav's, and although I think it may have sounded a little better somehow, I could still hear the distortion or whatever it is.

[gloval]

Don't be suprised if the manual doesn't state that information, sometimes you can gleam enough info from the BIOS
screen but in essence it's a trial and error.

You should be able to verify with other mp3 players like mpg123 and mpg321.

[Wedge_]

It seems like the USB being on the same IRQ wasn't affecting it at all. I tried it with USB disabled, and it made no difference. I did try a few other audio players, and it happens with every one

[gloval]

Did you try lowering the mixer volume.    Another possibility is the graphics card, that can be tested by going to the
console (init 3 or ctrl-ALT-F1) logging in then using mpg123.   I had a problem with SBPCI128 and XF4.0 IIRC
causeing problems.

[Wedge_]

Yeah, I tried changing the mixer volume. I managed to get the USB controller and soundcard on different IRQ's, but it doesn't seem to have helped. I'll go and try mpg123 like you suggested.

[lnx_author]

- hopefully this may help those of you with sound problems and Linux:

- there are three major projects/support for sound under Linux.:

1) the OSS code included with every Linux kernel; documentation is under the /usr/src/linux*/Documentation directory and you can read the SOUND-HOWTO at http://www.tldp.org

2) the Advanced Linux Sound Architecture sound code, found at http://www.alsa-project.org

3) very inexpensive, easy-to-install and easy-to-use commercial drivers at http://www.opensound.com (you can click on a few links, enter some cc info, then download the driver and receive a license file)

- each source has advantages and disadvantages, and i have used all three at one time or another on various machines

- if you are having trouble, try each one in the order above, with purchase of a commercial driver (usually $15[US] or so) as the last resort

- every Linux distribution will have a different method of sound configuration, but you can perform this task manually (as root) using the insmod and related commands

- some drivers (kernel modules) may offer or require optional arguments at load time

- laptop users are at the most disadvantage with troublesome/unsupported sound chipsets; PC users can often choose to install a different card

- Linux supports nearly every sound card made, but you should realize that if a sound chipset is not supported, it is NOT the fault of the Linux developer, but often is the result of a manufacturer that is unwilling/unable to release information about the chipset because of Non-Disclosure Agreement, trade or patent restrictions

- you should first try to use the tools included with your distribution to configure your sound card; failing that, try a google search on finding information about manually configuring your card/chipset under Linux; failing that, read the ALSA documentation regarding your sound card's chipset and try the ALSA software; failing that, check out opensound.com's (4Front-Technology's) web site regarding your chipset (there is a list of supported chipsets); failing that, write your own driver!

hth

[Wedge_]

I've tried all three at one point or another. At the moment I'm back to using the default OSS drivers. I would use the ALSA drivers instead, but every time I install them now, running any kind of sound app just locks up the system totally. The error messages mention a kernel panic, and it usually causes the caps lock and scroll lock keyboard indicators to flash. What does that mean? They used to work fine, and I'm installing them the same way I always have.

[gloval]

You've got a kernel panic,  yuk...  Can you check the /var/log/messages file to see if the panic message is stored in there if
not then you'll have to write the panic message down.

A panic is something that the kernel has detected as wrong but you may not have any recovery from, all that funny code
associated with it means something so if you can get that along with the System.map file you can decipher it.  If you are
stuck on the deciphering bit then attach them to an email and send it to karl_heyes@[removethisbit.]lineone.net

Can you verify whether it was due to the driver loading or using it.   You can load it separately with the modprobe
command, if that doesn't hang the machine then that tells us more.

As a side note, just to remove the possibility, are you using the binary nvidia drivers, if so then those have been known
to cause problems. Avoid loading those and try the sound playing, with oss and alsa.

[Wedge_]

I'll see if I can find the error message then. It's definitely not caused by loading the driver. I can modprobe it and everything is still fine, but as soon as I try to play any kind of sound, even from a console with mpg123, it just locks up like I said. I don't know why, since they used to work fine. I am using the nVidia drivers, and they were one of the first things I installed, so they've always been loaded. I'll get rid of them and try the sound again. Thanks for all the help