FC4 Odd noises from speakers: ALSA (was:I think I need some sound gurus)

[Bill Case]

Hi;

I have just clean installed Fedora Core 4 and I am having a problem with sqawks and hisses from my speakers. FC4 includes ALSA/gstreamer/amixer as sound driver and sound manager. I am using Ensoniq 5880 AudioPCI and an ATI TV Wonder tuner. So I have a cheap sound, TV and speaker setup. Sound and music are not a priority for me, I don't even own one music CD or a movie DVD so I know little about what the mixer provides. I have only selected PC Speaker and Line-in on my mixer gui.

I have received several ALSA patches from Fedora (including a ALSA prelink) since installing. Each patch improved the sound performance, but I still have annoying lowlevel hisses and sqwaks that seem to (in part) shadow my key strokes, event sounds, etc.

The noise comes from only my ancillary speaker (on the right) that is linked to the speaker (left) connected to my computer and that has the on/off button and volume control.

TV audio does not make these noises. I have moved my audio and TV tuner cards to PCI slots that are as far apart as possible -- that helped. So did resetting all sound components and wires. I believe (but I am not certain by any means) that there might be some extra ambient electrical radiation produced by my computer and particularly my ATI Wonder card that my sound card or outlets are picking up.

Is there a way to fix (or improve) my sound situation? Is it neccessary to isolate my sound card and are there tips and tricks for doing that?

Regards

[StarTiger]

First off, what is your hadware?

Next, check the mixer settings. try turning down your volume on some stuff, and also turn off imputs that you aren't using

[Bill Case]

Thanks StarTiger;

I thought my hardware description was in my signature; wrong mailing list. I've update my JL signature.

I have a Pentium 4 desktop with 640Mb ram.

Next, check the mixer settings. try turning down your volume on some stuff, and also turn off imputs that you aren't using

"I have only selected PC Speaker and Line-in on my mixer gui." As I say I am only using these two imputs. My volume on my mixer for both of these is about 50%. The volume on my main desktop speaker is set at 30% -- 40%. When using FC3 the noise level was there but very low. I didn't hear it unless I really cranked up the volume. Under FC4 it's annoyingly present in the background. At first I don't notice the noise much but after work for an hour or so it becomes very pervasive.

Regards Bill

[StarTiger]

What is your sound card and speakers?

Do you actually use your line-in source? On my system, I'll get that back round noise only when i have that port on. so turn it off when i'm not using it.

[Bill Case]

Thanks StarTiger;

Strange, tvtime sets line-in for the TV tuner's use as default (so they claim). I removed it from my mixer and didn't make a difference. As I said, I haven't paid much attention to sound. Could tvtime be using another line that I don't know about and do you know any command line queries that would tell me?

Regards Bill

[DSwain]

If you want to know what sound system you have, try lspci and look for something about a sound device. I think that's what you're asking for.

[Bill Case]

Thanks DSwain;

No that's not what I am asking. I know what sound card I have. See my original post.

My question is: If the tvtime literature says that tvtime uses 'line-in' by default, and I have turned 'line-in' off, and when I use tvtime it does not turn on the 'line-in' then how is the sound getting to my speakers?

Regards Bill

[Bill Case]

Hi;
Additional information: I have turned off every sound modality in my mixer. As long as I keep the volume of desktop speaker at 40% all the interference noise is gone or is at least sub-audible. I still can get computer event sounds and TV Audio. Which fixes my problem, but removes any use I might have for my mixer controls and leaves me completely perplexed over who or what is controlling my sound.

[banzaikai]

If I may...

You can turn off the PC Speaker input, since this is used for the connection from the mobo's "SPKR" header to the soundcard, which allows the PC speaker to sound off through your amplified speakers, instead of the internal speaker. If there's a "button" speaker element on your mobo, as most are now shipped that way, then you aren't using this feature, and probably never will. It also explains why the humming only comes from the right channel, since the speaker is a monophonic input.

Now, I've discussed this before, but it bears repeating: There's more than one way to get audio information around a computer - Analog and Digital. Your TV card sees that the Analog inputs are turned off, so it switches to the Digital way of getting it In/Out. Therefore, you still hear everything going on. This is called Digital Signal Processing, or DSP for short. You'll see it in your /sbin/lsmod somewhere.

Again, as everyone's mentioned, if you don't need it, then turn it off. And it doesn't hurt to try this, as you can always go back and turn it on again.

banzai "dedicated speaker" kai

[Bill Case]

Thanks banzaikai "If I may..."
You certainly may.
I left my computer on overnight and the noise is audiably back.

I ran lsmod | grep ^snd and got the following:
snd_ens1371 31649 1
snd_rawmidi 30305 1 snd_ens1371
snd_ac97_codec 75961 1 snd_ens1371
snd_seq_dummy 3653 0
snd_seq_oss 37057 0
snd_seq_midi_event 9153 1 snd_seq_oss
snd_seq 62289 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event
snd_seq_device 8781 4 snd_rawmidi,snd_seq_dummy,snd_seq_oss,snd_seq
snd_pcm_oss 51185 0
snd_mixer_oss 17857 1 snd_pcm_oss
snd_pcm 100169 3 snd_ens1371,snd_ac97_codec,snd_pcm_oss
snd_timer 33605 2 snd_seq,snd_pcm
snd 57157 12 snd_ens1371,snd_rawmidi,snd_ac97_codec,snd_seq_oss ,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss, snd_pcm,snd_timer
snd_page_alloc 9669 1 snd_pcm

plus; soundcore 10913 1 snd

plus;
bt878 10457 0
tuner 27121 0
bttv 161393 1 bt878
video_buf 23749 1 bttv
i2c_algo_bit 9289 1 bttv
v4l2_common 5825 1 bttv
btcx_risc 4937 1 bttv
tveeprom 13017 1 bttv
videodev 9537 1 bttv

I don't see DSP anywhere.

I checked my sound set up against the setup I have in Windows XP running on another hard drive. The sound for TV and cd's and events is perfect there.

WindowsXP
Vol Control: 40%
Wave: 40%
SW Synth: 95%
Line-in: Mute
CD Audio: 50%

All lines on my mixer gui are off. It seems to me you are saying that somehow my internal 'button speaker' is causing the interference and that I should turn it off. How?

This button speaker interference makes some sense to me because the 'noise' is still coming from my right speaker and if I listen closely the differnt *.wav (I think) bell sounds that are made at different computer events (e.g. opening a file) are scratch and fuzzy like they used to be on my old XT.

By the way, when I run the sound test gui, I hear sounds from both speakers as I should but the sound includes a lot of scratchy 'noise'. In FC3, the sound test was clear.

Regards

P.S. - A day later - I tried running Audacity and got the following error message: "There was an error initializing the audio i/o layer. You will not be able to play or record audio." Is there any clues in that?

[banzaikai]

I don't see DSP anywhere.

Oops. My bad. My setup doesn't show the DSP, either. You should find it in your /dev directory (ls /dev/dsp should list it). It may be part of the kernel.

It seems to me you are saying that somehow my internal 'button speaker' is causing the interference and that I should turn it off. How?

Err, no. What I was saying was that certain computers allowed you to use your sound card in place of the internal speaker (which used to be a real speaker that you'd hook up to the mobo header - new mobos have a small peizo installed, so you don't need this). If you don't have the two-lead cable from the "SPKR" pins on the mobo running to the sound card, then you don't have this, and should have the "PC Speaker" slider muted. Some modems have something like this, too, and you might want to check for a three-lead cable from the modem to your sound card, and temporarily disconnect it for testing. After that, the only other cable in or out is the CDROM, and that should be okay if it doesn't do it in Windows, but check it anyway.

...the 'noise' is still coming from my right speaker and if I listen closely the differnt *.wav (I think) bell sounds that are made at different computer events (e.g. opening a file) are scratch and fuzzy like they used to be on my old XT.

This may just be a case of over-modulation/saturation. On some cards, if the volume is up around 90-100%, then the amplifier starts clipping the waveforms passing through. I always set my sliders to about 75-80% to be safe. You could also try hooking up your Line Out to a (quiet) stereo amp and seeing what it sounds like. Maybe the output stage is flaky.

P.S. - A day later - I tried running Audacity and got the following error message: "There was an error initializing the audio i/o layer. You will not be able to play or record audio." Is there any clues in that?

It looks like you're running the OSS mixer, which means that you may have something using the audio device already. ALSA allows multiple device sharing by splitting things up into channels (there's another thread around here which shows how to edit your alsa config to do this). However, I'm also running OSS, and don't have this problem, but I'm not running event sounds or anything - just XMMS and the like.

banzai "the quiet company" kai

[Bill Case]

No, I am running the Alsa mixer. If 'line-in' is on I can hear my TV programs, but the event sounds have background noise. If 'line-in' is muted or removed, and PCM is unmuted all sounds (event, cd's etc.) are good and clear, but the TV can't be heard. TV time config file (tvtime.xml) permits /dev/mixercm but tvtime keeps switching 'line-in' to unmuted. I understand what you are saying about the TV card switching to 'line-in' if it can't detect analog inputs. But then why isn't it detecting my sound card properly and using PCM.

Regards Bill

[XiaoKJ]

why not like this, bill, post all the sliders for the alsa mixer for us to see. in text or pic form as you wish, so we can actually see where is your problem.

post not just the out put ones, but all of them.

Finally, thanks banzaikai --- that was indeed informational. But he may also need dmixer -- alsa alone doesn't allow for multiple connections to the soundcard

[Bill Case]

Hi;

Below is the output of amixer with TV on i.e. Line-in on. When I turn the TV off I have to mute Line-in or else I continue to get TV sound even when there is no video.

$ amixer
Simple mixer control 'Master',0
Capabilities: pvolume pswitch pswitch-joined
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 23 [74%] [on]
Front Right: Playback 23 [74%] [on]
Simple mixer control 'Master Mono',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback 0 - 31
Mono: Playback 0 [0%] [off]
Simple mixer control '3D Control - Switch',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control '3D Control Sigmatel - Depth',0
Capabilities: volume volume-joined
Playback channels: Mono
Limits: 0 - 3
Mono: 0 [0%]
Simple mixer control 'PCM',0
Capabilities: pvolume pswitch pswitch-joined
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 17 [55%] [on]
Front Right: Playback 17 [55%] [on]
Simple mixer control 'Line',0
Capabilities: pvolume pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 27 [87%] [on] Capture [on]
Front Right: Playback 27 [87%] [on] Capture [on]
Simple mixer control 'CD',0
Capabilities: pvolume pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 0 [0%] [off] Capture [off]
Front Right: Playback 0 [0%] [off] Capture [off]
Simple mixer control 'Mic',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Mono
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono: Playback 23 [74%] [off]
Front Left: Capture [off]
Front Right: Capture [off]
Simple mixer control 'Mic Boost (+20dB)',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'Mic Select',0
Capabilities:
Mono:
Simple mixer control 'Video',0
Capabilities: pvolume pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 0 [0%] [on] Capture [off]
Front Right: Playback 0 [0%] [on] Capture [off]
Simple mixer control 'Phone',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Mono
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono: Playback 0 [0%] [off]
Front Left: Capture [off]
Front Right: Capture [off]
Simple mixer control 'IEC958',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'PC Speaker',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback 0 - 15
Mono: Playback 0 [0%] [off]
Simple mixer control 'Aux',0
Capabilities: pvolume pswitch pswitch-joined cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Front Left: Playback 0 [0%] [off] Capture [off]
Front Right: Playback 0 [0%] [off] Capture [off]
Simple mixer control 'Mono Output Select',0
Capabilities:
Mono:
Simple mixer control 'Capture',0
Capabilities: cvolume cswitch cswitch-joined
Capture channels: Front Left - Front Right
Limits: Capture 0 - 15
Front Left: Capture 0 [0%] [off]
Front Right: Capture 0 [0%] [off]
Simple mixer control 'Mix',0
Capabilities: cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Capture channels: Front Left - Front Right
Front Left: Capture [off]
Front Right: Capture [off]
Simple mixer control 'Mix Mono',0
Capabilities: cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Capture channels: Front Left - Front Right
Front Left: Capture [off]
Front Right: Capture [off]
Simple mixer control 'External Amplifier',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'Sigmatel 4-Speaker Stereo',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'Sigmatel Surround Phase Inversion Playback ',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]

To restate the problem:

On 'line-in' my speakers hiss and squawk and the event sounds are terrible but I
have no background noise problems when 'line-in' is muted and PCM is open.
tvtimes keeps reverting to line-in.
Audacity gives error: "There was an error initializing the audio i/o layer. ..."
Every time I logon, PCM gets muted in my mixer gui.
CD's play fine.
My tvtimes configuration file /etc/tvtime/tvtime.xml is set to <option
name="MixerDevice" value="/dev/mixer: pcm"/>

Soundcard detection responds with the test sound + a very scratchy background.

gstreamer-properties gui (Multimedia Systems Selector) test gives me the following:

With PCM on and 'line-in ' muted:
Output ALSA pipeline alsasink = good clear sound.
Input ALSA pipeline alsasrc = no sound (crashes gui)

With PCM muted and 'line-in ' on:
Output ALSA pipeline alsasink = sound + hissing background.
Input ALSA pipeline alsasrc = no sound (crashes gui)

When I run the above gstreamer-properties test as root user, I get no alsasink
or alsasrc recognition at all.

permissions on /dev/dsp /dev/audio /dev/mixer all crw-------

At startup, from dmesg during udev initialization audio is intialized on bttv
and audio takes an uncommonly long time to get set.
My understanding is that it should start with ALSA.

I have run gst-register-0.8 as root. It made no difference.

Regards Bill

[Bill Case]

Hi again;

From the fedora mailing list; someone mentioned that his /etc/udev/devices included his nivida sound card. While mine is Ensonq, my /etc/udev/devices file is empty. Is this significant?

Regards Bill