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krishna.murphy
04-07-2010, 12:55 PM
I use the Preferences-System Settings-Multimedia mechanism to control which "sound card" to use, but it will simply fail to work with my headset occasionally. If I use the "Test" feature when the device is clicked as shown in the attachment, I get the test sound in the headphones. But it just now won't give me the sound from a YouTube video. What gives???

Krishna

klaus2008
04-07-2010, 06:02 PM
I have two sound cards, too. One is integrated in the mainboard and the other one is a USB device with an amplifier for my record player. With PulseAudio I am able to switch over to a different sound device for output.
I did the following in order to install PulseAudio.


sudo apt-get update
sudo apt-get -t testing install pulseaudio paman pavucontrol paprefs

Afterwards I created a file /etc/asound.conf with the following configuration as described on the page http://pulseaudio.org/wiki/PerfectSetup:


pcm.pulse {
type pulse
}
ctl.pulse {
type pulse
}
pcm.!default {
type pulse
}
ctl.!default {
type pulse
}

I rebooted the system. In the menu "Sound & Video" I found the "PulseAudio Volume Control" which I use to select the output device.

klaus2008
07-26-2010, 06:02 PM
I found a simpler way to change the sound output device than using PulseAudio.
cat /proc/asound/cardsshows the sound cards installed in the system. In my case the sound card I want to use has the number 1. I create a configuration file /home/knoppix/.asoundrc with the two lines


defaults.ctl.card 1
defaults.pcm.card 1
I can adjust the volume with the program alsamixer (or aumix). After restarting the Xserver the volume control in the LXPanel works with the new sound card. If the the web browser is running using the flash plugin while I change the settings for the default sound card then I have to restart the web browser in order that the flash plugin uses the new sound card for playback.

utu
07-26-2010, 06:29 PM
Here a few more ideas for you, Krishna:

I use the following /etc/rc.local to 'max-out' audio volume on my laptop:
added sudo amixer sset 'Master' 64;
sudo amixer sset 'Speaker' 64; and
sudo amixer sset 'PCI' 255.

Audio settings can be viewed and/or changed in an LXTerminal with 'alsamixer'.
(I don't know if driving alsamixer values 'into the red' is harmful;
I keep the apparent volume about the same as in Win7 usage.)

krishna.murphy
07-26-2010, 09:34 PM
Thanks! I hope this will help others, too.

Cheers!
Krishna :mrgreen:

krishna.murphy
07-26-2010, 10:49 PM
Here a few more ideas for you, Krishna:

I use the following /etc/rc.local to 'max-out' audio volume on my laptop:
added sudo amixer sset 'Master' 64;
sudo amixer sset 'Speaker' 64; and
sudo amixer sset 'PCI' 255.

Audio settings can be viewed and/or changed in an LXTerminal with 'alsamixer'.
(I don't know if driving alsamixer values 'into the red' is harmful;
I keep the apparent volume about the same as in Win7 usage.)

I checked my settings as follows:

cat /proc/asound/cards
0 [V8237 ]: VIA8237 - VIA 8237
VIA 8237 with CMI9761A+ at 0xe400, irq 22
1 [Headset ]: USB-Audio - Logitech USB Headset
Logitech Logitech USB Headset at usb-0000:00:10.2-1, full speed
knoppix@Microknoppix:~$ amixer
Simple mixer control 'Master',0
Capabilities: pvolume pswitch pswitch-joined
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono:
Front Left: Playback 23 [74%] [-12.00dB] [on]
Front Right: Playback 23 [74%] [-12.00dB] [on]
Simple mixer control 'PCM',0
Capabilities: pvolume pswitch pswitch-joined
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono:
Front Left: Playback 23 [74%] [-12.00dB] [on]
Front Right: Playback 23 [74%] [-12.00dB] [on]
--------snip--------
I'm wondering how wise or unwise exceeding a value of 31 would be, given what I see here. I have different hardware now than I did before, with an external amp to boost things, but I'm still interested. Thanks again, and

Cheers!
Krishna :mrgreen:

utu
07-27-2010, 12:21 AM
Krishna,

Note: I max out my speakers, but not headphones.
Speaker output on my laptop is too weak otherwise,
and if it seems louder than I use with Win7, I
just turn it down with panel VC. Seems safe enough.

Having maxed my PCM, I can't say for sure I have
not hurt the headphone channels. But I don't
have any headphones, and probably won't use that
capability anyway.

I'm really fond of the nice gui that alsamixer
shows on an LXTerminal.

daveca
03-23-2011, 02:20 AM
thanks to Klaus2008s file .asoundrc I now have USB 1.1 headphone audio in Knoppix 6.4.4 Main goal accomplished. The Penguin REALLY rocks now that Ive learned how to make a proper flash drive install! BUT.... the volume control applet has vanished from the task bar, although it still appears in the applet list. Adding another volume control didnt accomplish anything except having two that dont appear. "Aumix" does nothing to adjust the USB HS volume, nor does "Mute all" have any effect. The HS volume control does not work. I hear Todd Rundgren in Stereo but I cant "crank it up" Starting Alsamixer in Terminal allows me to change the volume, "in the red" works at 2 dB! I can croon along with Chicago and not hear how horrible I sound. HS volume control still doesnt work. Unfortunately the arrow keys follow focus so the mixer cant be adjusted when not focused on Terminal. Q. How to get volume control on the Taskbar a/o a control in Aumix??

utu
03-23-2011, 02:34 AM
So, what happens when you enter
alsamixer
into an lxterminal?

daveca
03-23-2011, 05:16 AM
Alsamixer 1.0.23 - it works. can change HS volume, but its klunky, I Alt-Tab - Arrow it to change volume when the mixer is in the background. There is an F6 invoked "select sound card" menu item in Alsamixer which appears to change the card used, maybe thats an alternative to writing the .asourc file? ill try it tomorrow.