Help me to comprehend the audio system in 64 Studio

  • wendalltan
Posted: Mon, 02/16/2009 - 17:39
Hi everyone, I've been running 64 Studio for a few weeks now and am really enjoying it. I've amassed what I hope to be all the software and plugins needed for recording my next album using Reaper as my DAW and a bunch of VST plugins, etc. Now that I've been using things for a while, I have some questions about the audio system and how to hopefully reset Jack/ALSA when I crash Reaper (happens every few hours) without a reboot. So 1st question, completely off topic from making music: I have Totem and VLC installed. Totem never works, I get the error: Totem could not play [file name]. The audio device is busy. Is another application using it? I have no other apps running that do anything with the sound card. If I fire up Amarok and play back some music, then open Totem again, the file plays fine (no error message), but I get no audio from the video player. VLC works well (no errors), but again if I have anything using audio (amarok) I get no sound from the video player. Amarok is configured currently to use the Xine OSS engine. It appears that some of my apps use OSS (totem(?), amarok, vlc) and some use ALSA (jack). I'm not quite sure where Jack fits into this equation, or maybe it doesn't. It seems like OSS and ALSA step on each others toes while trying to handle audio duties. It'd be nice to just use ALSA since that's what I use for my audio recording. Is there a way to do this, to remove OSS completely or something like that? Next question, I'm using Reaper and jackbridge to feed into Jack when I'm working on my audio recording. Reaper crashes once in a while and takes Jack down with it. jackbridge seems to continue to run. If I restart Jack (using qjackctl), the interface will pop up and I can start the server, but it hangs for about 10 seconds and then qjackctl exits without any messages. If I close jackbridge from my previous session, jack will run fine until I start jackbridge again, and then it will hang and exit just like I described above. I found the alsa-utils command in my /etc/init.d/ directory and have tried to use that to restart my sound card. The command executes successfully, but the above problems persist. I'm hoping I can find a way to either stop jackbridge from locking up Jack when Reaper crashes, or maybe find a command that will restart Jack/ALSA/whatever and allow me to start Reaper up again and continue with my work rather than having to take a few minutes to reboot my machine. Any help with these issues is greatly appreciated. I hope to get a good understanding of how the Linux audio system(s) work, as I'm pretty ignorant of that right now. Overall I'm really happy with 64 Studio and have had a great time being really productive with it the last couple of weeks.

Reaper...

  • Quentin Harley
  • 05/24/07
  • Mon, 02/16/2009 - 21:12
Although I keep a copy of reaper handy when I get colaborations form the windows world, I almost exclusively work in the native applications, Jack, Ardour, Jamin, rosegarden, audacity etc. Check out the 64 Studio manual pages... there is a nice breakdown of how things work in 64 studio, and where jack, ALSA and the rest fit in. After you get the hang of Jack, you'll feel slightly irritated when you have to work on a system that is not jack enabled...