OK, So as per these several suggestions, I've now tried the US428 with a vanilla 2.6.11, a 2.6.11 with Ingo's preempt patch and full preemption, nrpacks=4, apm and acpi not compiled in the kernel, and without my usb ethernet card plugged in. I'm still getting the "Sequence Error!" messages, then a couple seconds later qjackctl dissapears. I still haven't tuned the IRQ stuff, because I'm still getting the error of: execvp: No such file or directory failed to execute pidof "IRQ 8" when I try to execute chrt -f -p 80 'pidof "IRQ 8"' I'm not sure what do do about that one, and google and man don't seem to help me much. Any thoughts? Thanks, -spencer On Thu, Mar 03, 2005 at 06:58:08PM +0100, Karsten Wiese wrote: > Am Donnerstag 03 M?rz 2005 16:32 schrieb Spencer Russell: > > On Thu, Mar 03, 2005 at 12:41:17PM +0100, Karsten Wiese wrote: > > > > > > can you check if this error doesn't happen, when modprobing like > > > $ modprobe snd_usb_usx2y nrpacks=4 > > > ? > > > nrpacks=1 and "rawusb mode" are irrelevant if you run jack with moderate latencies > > > as above "-p1024 -n2" and 2 inputs. > > > > > > > With nrpacks=4, it seems to last slightly longer before giving > > the "Sequence Error!" and "Most propably some urb of usb-frame > > 935 is still missing" > > > > try with apm and acpi disabled. > append "apm=off acpi=off" to the kernels boot parameter line. > on laptops lots of things happen "beghind the scenes" . > "apm=off acpi=off" made a big differenc here when I used 2.4 kernels. > > > > What kernel are you using? If its not 2.6.11 you might give that a try. > > > > Every time I've tried using a 2.6 kernel on this machine, I get > > these random lockups that I can't figure out, so I'm using 2.4.26 > > with lowlatency, preempt, and givecap patches. I'll try 2.6.11, > > and see how that goes. > > also on 2.6.11 you'd disable apm & acpi like above to try to get rid > of those random lockups or "Sequence Error!"s. > > > > > Rui said a while ago that he was getting a similar message, until > > he tuned the IRQ priorities, but I've been googling around and I > > can't figure out how to do it. I tried > > chrt -f -p 90 'pidof "IRQ 0"' > > as directed on some website, but it just returns > > > > execvp: No such file or directory > > failed to execute pidof "IRQ 0" > > this is for the realtime kernel patches by Ingo Molnar. > I may be wrong, but I'd suggest you get it running on 2.6.11 before you > proceed with the realtime kernels. > Plain 2.6.11 gives me better low latency (and better behavior with acpi enabled too) than > patched 2.4 kernels. lots of Ingo's enhancements are in 2.6.11 already. > > Still the very basic mode with > $ modprobe snd_usb_usx2y nrpacks=4 > must work flawlessly with 2 in / 2 out jack like > $ jackd -R -dalsa -dhw:0 > on a plain kernel as first step. > > > > srussell@slingshot:~$ lsusb > > Bus 001 Device 001: ID 0000:0000 > > Bus 001 Device 002: ID 07a6:0986 ADMtek, Inc. AN986 Pegasus Ethernet > > Bus 001 Device 005: ID 1604:8001 Tascam US-428 Audio/Midi Controller > > Your ethernet is also on usb! > Usb audio is enough to fully occupy an USB 1.1 bus. > Try with us428 as the only usb client (without that usb ethernet). > > cheers > Karsten > >
