On Sun, Feb 08, 2009 at 01:55:36PM +0100, Johannes Wiedersich wrote: > Thanks for your reply, Joel! > > Joel Roth wrote: > > On Sat, Feb 07, 2009 at 03:54:41PM +0100, Johannes Wiedersich wrote: > >> Hallo all! > >> > >> On switching my usb sound card to 24bit audio, all applications using > >> the card will crash/segfault: > >> > >> $ aplay led_zeppelin-houses_of_the_holy-a.wav > >> Playing WAVE 'led_zeppelin-houses_of_the_holy-a.wav' : Signed 16 bit > >> Little Endian, Rate 44100 Hz, Stereo > >> Segmentation fault
> > There are many wrinkles and ways of solving problems > > with Linux audio. > > > > At the ALSA level, the 'default' pcm device as provided by modern > > kernels automatically performs format conversion. Maybe some > > of the others, too. > > > > $ aplay -L > > > > provides a list of your system's ALSA pcm sound devices. > > $ aplay -L > surround40:CARD=USB2448,DEV=0 > PHASE 26 USB(24/48), USB Audio > 4.0 Surround output to Front and Rear speakers > surround41:CARD=USB2448,DEV=0 > PHASE 26 USB(24/48), USB Audio > 4.1 Surround output to Front, Rear and Subwoofer speakers > surround50:CARD=USB2448,DEV=0 > PHASE 26 USB(24/48), USB Audio > 5.0 Surround output to Front, Center and Rear speakers > surround51:CARD=USB2448,DEV=0 > PHASE 26 USB(24/48), USB Audio > 5.1 Surround output to Front, Center, Rear and Subwoofer speakers > surround71:CARD=USB2448,DEV=0 > PHASE 26 USB(24/48), USB Audio > 7.1 Surround output to Front, Center, Side, Rear and Woofer speakers > > looks fine to me, but there is no line that looks like plain 'stereo'. > > If I switch to 16 bit on the sound card, sound works and shows this: > > $ aplay -L > default:CARD=USB1648 > PHASE 26 USB(16/48), USB Audio > Default Audio Device > front:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > Front speakers > surround40:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > 4.0 Surround output to Front and Rear speakers > surround41:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > 4.1 Surround output to Front, Rear and Subwoofer speakers > surround50:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > 5.0 Surround output to Front, Center and Rear speakers > surround51:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > 5.1 Surround output to Front, Center, Rear and Subwoofer speakers > surround71:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > 7.1 Surround output to Front, Center, Side, Rear and Woofer speakers > iec958:CARD=USB1648,DEV=0 > PHASE 26 USB(16/48), USB Audio > IEC958 (S/PDIF) Digital Audio Output > null > Discard all samples (playback) or generate zero samples (capture) > > > Now for your system, you should reboot or unplug and replug > > your USB sound device after changing to 24-bit to ensure the > > ALSA driver reads the 24-bit configuration. > > Done, redone and repeated again ;-) > > So far without success. It seems to be either a config problem or a bug > (alsa or kernel?). > > > You can also choose to specify in your $HOME/.asoundrc file what the > > output format to the soundcard should be for a particular > > device. > > How to do that? > > http://alsa.opensrc.org/index.php/.asoundrc > > shows how to set the sample rate, but that seems to fine, here. According to: http://alsa.opensrc.org/.asoundrc#Default_PCM_device ALSA usually maps 'default' (missing in your listing with card set to 24-bit) to plughw:0,0 plughw:0,0 gets the sample-rate conversion, in comparison to hw:0,0 which is the naked hardware device. (hw:0 is usually shorthand for hw:0,0.) So try this, too: aplay -D plughw:0,0 somestereo.wav If it works, you might try creating a file .asoundrc in your home directory with the line: pcm.default! plughw:0,0 or from the .asoundrc pages: pcm.default! surround40:USB2448 These have a chance, since the OSS emulation is usually directed to the 'default' device which you say is missing in the aplay -L listing when the card is in 24-bit mode. > > I find the Ecasound provides an easy way to handle > > format conversions. > > > > $ ecasound -i cd-stereo.wav -f:s24_le,2,44100 -o alsa,hw:0 > > Playing a wav with this command line works. Is the playback speed the same when you use -f:s24_le,2,48000 ? How about the other way, recording something. ecasound -i alsa,hw:0 -f:s24_le,2,48000 -o test.wav Maybe your microphone is mono so you'll use -f:24_le,1,44100 to save recording a blank channel. > > Ecasound is a swiss-army knife of audio processing, > > can do many common audio processing tasks. > > > >> kaffeine, amarok, xine etc. all just crash. > > > > It sounds like a configuration problem, maybe ALSA > > needs to be told that your USB soundcard is set to 24 bits. > > How to do that? > > > This suggests that you are 99% there, since your ALSA driver is > > already taking care of converting the signal from 44100 to > > 48000 Hz. > > > > Good luck with that last 1%. 24 bits will help if you > > are doing multitrack stuff. In which case you might > > consider Audacity (friendly GUI), Ardour (total pro) > > or even Nama (http://ecmd.infogami.com) which I have > > developed using Ecasound for audio processing. > > Audacity doesn't crash :-) , however, my speakers start to beep and > crack in all unpleasant sounds imaginable, as soon as I start it > (without trying to play or record anything). if you type lsmod | grep snd you'll get a list of all the sound modules that are loaded. I think Audacity plays through OSS emulation (via a sound device called /dev/dsp). > I should have told before, that the sound card works fine on 24 bit on > etch, but NOT on lenny. I just checked with the etch system of my girl > friend. There it works 'plug and play' without a glitch and without > having to configure anything. That is part of the joy of it, and a reason why if someone has a production system that they use for real work, they don't casually upgrade. hope this helps, Joel > Thanks, > > Johannes > -- Joel Roth -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
