On Sun, 1 Dec 2013, wempwer@xxxxxxxxx wrote: > On my way to become an advanced Linux user I started to learn > ALSA. However, it seems that ALSA, and sound system in general on > Linux, is in a pretty bad state at the moment. Here are the examples - > don't get me wrong, fix me if I got things wrong: The write up it poor. Also itself operages quite well. > > 1) my work computer with Ubuntu has HDA Intel PCH soundcard > installed. Moving PCM slider in alsamixer or muting it has no > effect. This happens both when pulseaudio server is stopped and pulseaudio is NOT alsa. > running. Moreover, manipulating volume slider inside pavucontrol > results in higher volume than when Master and Speakers are set to > maximum in alsamixer alone. That means, if I set a maximum volume > inside pavucontrol I can hear sound louder because even if volume is > set to maximum in alsamixer it is only about 50% in pavucontrol. > > 2) my home laptop HP Pavilion DV6 3015ew with Slackware has HDA ATI SB > soundcard installed. Here, moving PCM slider in alsamixer changes > volume correctly but PCM cannot be muted. Nothing happens in alsamixer > when I press `m', and amixer says: Probably because your soundcard has no mute. > > $ amixer set PCM mute > amixer: Invalid command! > > pulseaudio is not running here. Why is PCM observed behavior not > coherent between 1) and 2) ? > > 3) my Toshiba n550d netbook has 2 soundcards - alsamixer shows > "HD-Audio Generic" and "HDA ATI SB". What is bad is that the first > card is set as default but it has no controls in alsamixer apart from > "S/PDIF". Why this has happened? It brings some problems in programs > that pick the first available card and treat it as default. For > example, mocp says: > > Running the server... > Trying OSS... oss is not alsa. > > FATAL_ERROR: No valid sound driver > > FATAL_ERROR: Server exited > > I needed to the following to $HOME/.moc/config: > > AlsaDevice = hw:1,0 And that solves it? Seems to be a problem with mocp. > > 4) What's the relationship between Alsa, PulseAudio and OSS? On my HP Alsa is the sound card driver layer in Linux. Oss was another sound card driver completely different from alsa, but alsa developers created an OSS simultion layer so that sound systems which expected to use oss could do so. It is a translation layer which translates oss to alsa commands. Pulse audio is an entirely separate layer above all of those. It was developed to allow mixing of sound sources and as one unified layer so that all programs would see the same sound interface, no matter what the hardware underneath was. Unfortunately its plans and its execution do not always coincide. > Pavilion laptop I installed Linphone, a cool SIP client but I wasn't > able to use it with my in-built mic until I set capture device to > "OSS: /dev/dsp" in Linphone. I was looking for some general > information on how to configure a microphone and I found this: > http://alsa.opensrc.org/Record_from_mic. However, this guide contains > expressions such as "I am not sure about that" or "Other things to > try: " and a list of random thoughts follows. And about PulseAudio, I > remember back in days that killing PulseAudio was the very first thing > to do after starting the system to able to hear any sound at all. It has apparently gotten better but still can be problematic. Note that its purpose was precisely to hide all of the sound details from the user. Remember that there are probably about 1000 different sound cards out there, each of which decides to do things differently because the manufacturer/developer knows better than everyone else ( or maybe so that they can be proprietary and stop anyone else from doing anything with the soundcard so that they are the only source for software.) > > 5) My parents have Acer Aspire d255. It has some problems with > in-built microphone - it doesn't work. This bug describes it: > https://bugs.launchpad.net/ubuntu/+s...er/+bug/940841. Does anybody > know if this problem is solved now in new kernel, new ALSA or is it > solved at all? My parents are computer illiterate, they used to have > Windows 7 Starter on this machine but it took it like 15 minutes to > start so I removed it and installed Ubuntu for them. Now I have to > explain to them why the microphone doesn't work out of the box. No idea. See my answer to 4. > > 6) A few months ago I got myself Creative bluetooth speakers. I have > the following in my ~/.asoundrc.conf: > > Quote: > pcm.bluetooth { > type bluetooth > device 00:02:3C:20:1D:5E > } > > pcm.!default { > type plug > slave.pcm "bluetooth" > } > > Some programs such as xmms2 can pick these settings correctly and play > music on speakers, but some others such as mplayer can't do that and I > always have to pass "-ao alsa:device=bluetooth" what's really annoying > (I could create an alias for that but it's just a workaround and not a Sorry, telling theprogram which sound output to use is a "workaround"? Surely you do not expect your computer to read your mind as well. Your computer has other sound output devices. How is it to know which one you want unless you tell it? > real solution). What's even more, I can't play sound in 2 programs > simultaneously - only one program at a time can play sound. If I open > a flash video in Firefox, I need to close it before I can play a song > in xmms2. xmms2 for example is saying: That was one of the reasons why pulseaudio was developed, to allow simultaneous playing of multiple sources. Alsa is a "single source" system. It does not have a mixer front end. How to tell pulseaudio to also handle the bluetooth I do not know. It is probably possible. > > Please check that: > > Your sound card is configured properly > You have the correct output plugin selected > No other program is blocking the sound card > > That's all. I am quite worried about all of these. It makes me thing > that Linux is still not ready for wider adoption amongst casual users. > > -- William G. Unruh | Canadian Institute for| Tel: +1(604)822-3273 Physics&Astronomy | Advanced Research | Fax: +1(604)822-5324 UBC, Vancouver,BC | Program in Cosmology | unruh@xxxxxxxxxxxxxx Canada V6T 1Z1 | and Gravity | www.theory.physics.ubc.ca/ ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349351&iu=/4140/ostg.clktrk _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
