On Sun, Jun 20, 2010 at 7:05 PM, Rick Bragg <<a href="mailto:lists@gmnet.net">lists@gmnet.net</a>> wrote: <div class="gmail_quote"><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> Hi, I am looking at the documentation for my M-Audio Fasttrack Pro and it can do up to 96k 24bit recording, however, I am trying to fire it up with qjackctl and it I can't get it to do anything other than 16 bit little endian 44100 sample rate. I get an error in the messages that says the playback and capture sample rates do not match. I am using the latest Ubuntu 10.04LTS with Following are my "messages" Does anybody know how I can get the most out of this device? Thanks Rick </blockquote><div> </div><div>Not sure why your playback rates and capture rates are different, and I'm also not sure why it settles at 16bit. I've never used a USB interface with JACK before. However, I can maybe give you some info on other issues that might help. First, even though your interface (and many others) can do 96khz, you probably should not use that high a rate. The theoretical improvements in quality do not outweigh the negatives. It's a long topic, so I won't get into it here, except to say that there's plenty of material to read on the Internet about it (such as this informative thread at the Ardour forums: <a href="http://ardour.org/node/3341">http://ardour.org/node/3341</a>). This is probably one of the reasons you are getting so many X-runs. I would suggest just using 44.1 khz. Other than that, it would be nice to know more details about your set-up. In particular: -What kernel are you using? If you're using an RT kernel, make sure that a) you have JACK set to use realtime, and b) you have some sort of script installed that sets realtime thread priorities (such as the rtirq-init script in the repositories). If you're using Ubuntu Studio, you should already have this script installed. -If you've got Network Manager installed (which you probably do), make sure to disable networking prior to starting JACK. You can do this via the context menu by right-clicking on the notification applet. Network Manager has been known to cause issues with the sound server. </div></div> Those are the easy things to try out. Hopefully they improve your situation. -- -Brian David