On Fri, May 3, 2013 at 2:14 PM, Fons Adriaensen <fons(a)linuxaudio.org> wrote:
  I'm preparing a seminar that will take place
tomorrow (4 May),
 it will involve live mixing of surround sound using Ardour.
 While setting up the PC to be used, two problems occured.
 The first one is solved, but its cause remains misterious.
 A some point it appeared that the sound card (HDSP-MADI,
 used every day since years) had decided to meet its creator.
 Every program trying to access it - from jackd to aplay -L
 not only blocked, but turned out to be impossible to kill.
 Replaced the card - same result. It turned out to be a
 corrupt /var/lib/alsa/asound.state. The systemd service
 doing the 'alsactl restore' while booting choked on it,
 blocked, and  this apperently blocked all others trying
 to use the card later. What I don't understand is how alsactl
 exactly failed, and why these processes seemed to be immune
 to a 'kill -9'.
 The second one is an Ardour2 session that worked perfectly
 on another similar PC, but becomes completely unresponsive
 on the one to be used. It has four mono tracks and three
 10-channel ones, and little else. DSP load is not the problem,
 it's less than 15%. Things look like it's the graphics. When
 Ardour's playhead reaches the right end of the editor window,
 it takes something like 5 seconds for the editor display to
 update - everything seems to freeze during that time but audio
 is not interrupted. Same when trying to scroll or change the
 zoom factor. Video card is Nvidia GeForce 7300, indeed quite
 old, but the same PC does full-screen HD youtube videos without
 problem. Video driver is nouveau as nv seems to be no longer
 supported by Archlinux. I'm pretty sure this system didn't have
 such problems when it was using nv. OTOH nouveau works very well
 on other systems... I could try and install the proprietary
 Nvidia driver, but with just some hours to go I'd rather not
 take any risks...
 Any hints ?
 Ciao,
 
Fons, sorry if this reply didn't come in time, but FWIW, Non-Timeline can
now import Ardour sessions (audio tracks and regions) and should have
significantly faster graphics, esp. on older hardware.