On 05.02.2013 23:34, Martin Topholm wrote: > I'm having an issue with unrealiable probing of my Logitech Z-5 USB > speakers. > > With Arch Linux (kernel 3.7.5-1-ARCH) the mixer usually gets attached, > but the audio output interface doesn't (aplay -l list is empty). Building > a custom kernel with CONFIG_HZ=100 "fixes" the problem and both mixer > and audio output interface are reliably recognized every time. That's really strange and I doubt this is realted to CONFIG_HZ really. Are you totally sure about that? > alsa-info for 3.7.5-1-ARCH is located at > http://www.alsa-project.org/db/?f=6ac3bf30b27c6dbe4917b09a677bf695761d5eff > > alsa-info for 3.7.5-1-MPH is located at > http://www.alsa-project.org/db/?f=df0e3b5db470b86844c0c714c83bcde71f4da90e > > I originally encountered this problem with Ubuntu, when they changed > from CONFIG_HZ=100 to CONFIG_HZ=250 (I think it happened sometime between > Natty and Precise). In Ubuntu the speakers could sometimes connect if > I repeatedly unloaded/loaded snd_usb_audio and removed re-attached > the speakers. Each time it failed dmesg showed: > > [ 11.568216] cannot find UAC_HEADER > [ 11.568230] snd-usb-audio: probe of 4-2:1.0 failed with error -5 Which tells you the descriptors of your device is broken. But that should reliably fail, not just occasionally. And also not depending on CONFIG_HZ. Can you please send the output of 'lsusb -v'? Daniel ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user