Joel, About the only thing I can think of to try (other than an IDE drive) is to adjust the latencies of the SCSI controller and the sound card. Use setpci. I think I've got an example on my web site and, IIRC, a link to an article on setting latency. Jan On Mon, 31 May 2004 23:00 , Joel White <cv223@xxxxxxxxxxx> sent: >Aha, a thread convergence! > >I started the "Ardour..." thread lamenting long xruns under the 2.6 >kernels. Based on recommendations on the list, I went back to a 2.4 >kernel, still having the occasional long xrun. In the "XRuns..." >thread, the following from a post by Jan Depner caught my eye: > >"What kind of disk drives? Adaptec SCSI controllers can give you >problems with xruns." > >Uh-oh. I'm using an Adaptec controller on my main board (a 7890). With >a little digging, I came up with the following from the ST Audio website >(http://www.staudio.de/kb/english/conflicts/): > >"The famous Adaptec 2940 SCSI controller series is causing performance >problems when installed in the same system as our DSP24 series and when >the audiodata is stored on a SCSI-HDD connected to the controller. To >get good results in benchmark tests, the Adaptec controller keeps steady >access to the PCI bus. The result is a reduction of data transfer of >other PCI cards like the DSP24 hardware. This means that the ASIO/MME >buffer size (which is the latency) needs to be set to a relative high >value to avoid stuttered audio playback and drop-outs during recording. >The performance problems can be reduced if both the DSP24 and the >Adaptec controller both have a unique and unshared IRQ. Still the >performance will not be as good compared to the regular onboard >IDE-controller of a modern mainboard. This means that the best solution >is to use a IDE-HDD to save the audiodata from within your recording >software. The simple presence of the controller (that is used while the >audiodata is stored on a IDE-HDD) is no problem." > >Uh-oh again. The 7890 is the on-board version of the 2940. I thought I >had the xruns pretty much under control with the 2.4 kernel, then I >picked up a M-Audio Delta 1010LT (I was jonesing for the 8 channels of >input!). Ugh. I can't record more than a few seconds of 8 channel >input before a 100msec+ xruns brings everything to a halt. Even >recording 2 channels won't make it through a 4:00 min song. > >So, am I completely hosed with my Adaptec SCSI drive setup? Anybody >have any insight into these Adaptec controllers? I've fussed with the >setpci latency_timer settings (from Jan Depner's "Installing and >configuring ALSA, JACK, & Ardour..." web site), but still see long >xruns. Trying an IDE drive is not that simple, as I don't have any >drive slots left in the box (I've got 4 SCSI drives setup as a RAID). >So, I'd like to exhaust all possibilities before trying new drive >configurations. > >Any thoughts/ideas/suggestions would be _greatly_ appreciated! > >Thanks, > >Joel > > >