[linux-audio-user] USB-audio-card notches

Hi, it's easter time, so I play a bit with aeolus ;-) . Anyway, I have a Dell Inspiron 8200 with a vanilla 2.6.10 kernel. The only patch applied is the LSM-RT-patch. The Inspiron offers a USB 1.1 port. A USB 2.0 hub is connected to it. On the hub, there are currently two USB devices: * A Midisport 8x8 * A Terratec Aureon 5.1 USB On top of the card, I start JACK. I tried various settings, currently I use /usr/bin/jackd -v -R -P5 -p16 -t2000 -dalsa -dplughw:2 -r48000 -p256 -n3 -P As soon as I play through JACK, I get notches, regardless if it was alsa modular synth, Aeolus or xmms. The log shows lines like the ones attached below. So I stopped JACK and tried to use the device in ALSA only mode. * xmms now plays fine on the device hw:2,0 * ams and aeolus produce a lot of xruns and I get no audio output using hw:2,0 * when starting ams as ams --soundcard plughw:2,0 --rate 48000 I get a lot of xruns again and the sound is worse (more notches) as when running ams or Aeolus on top of JACK * notches also appear as soon as I try to record audio input using qarecord connected to JACK * when using plughw:2,0 and a samplerate of 48000 (44100 will not work) in the aeolusrc, I get proper output at least by Aeolus I could need a helping hand by making the card working properly. Anyone an idea where I can put the screwdriver? I did also have a look into the modinfo of snd-usb-audio, but I cannot detect a parameter to tell it, mybe, to use a samplerate of 48000 or similar settings: modinfo snd-usb-audio author: Takashi Iwai <tiwai(a)suse.de> description: USB Audio license: GPL parm: index:Index value for the USB audio adapter. parm: id:ID string for the USB audio adapter. parm: enable:Enable USB audio adapter. parm: vid:Vendor ID for the USB audio device. parm: pid:Product ID for the USB audio device. parm: nrpacks:Max. number of packets per URB. parm: async_unlink:Use async unlink mode. vermagic: 2.6.10ce SMP PENTIUMII 4KSTACKS gcc-3.3 depends: snd-usb-lib,snd-pcm,snd Every wee small hint (even RTFM ;-) is much appreciated. BTW: Is this the right place, or should I post it to LAD? Best regards ce JACK log: client qjackctl-13201: start_fd=5, execution_order=0. client aeolus: in subgraph after qjackctl-13201, execution_order=1. client qjackctl-13201: wait_fd=18, execution_order=2. client alsa_pcm: internal client, execution_order=3. -- jack_rechain_graph() 23:10:59.394 Audio active patchbay scan... load = 11.6229 max usecs: 636.000, spare = 4697.000 load = 11.3899 max usecs: 595.000, spare = 4738.000 load = 11.2547 max usecs: 593.000, spare = 4740.000 load = 11.5246 max usecs: 629.000, spare = 4704.000 load = 11.4345 max usecs: 605.000, spare = 4728.000 delay of 5962.000 usecs exceeds estimated spare time of 4728.000; restart ... 23:11:05.205 XRUN callback (4). load = 11.9895 max usecs: 669.000, spare = 4664.000 load = 12.4077 max usecs: 684.000, spare = 4649.000 load = 11.8479 max usecs: 602.000, spare = 4731.000 load = 11.7931 max usecs: 626.000, spare = 4707.000 load = 11.8219 max usecs: 632.000, spare = 4701.000 load = 11.9676 max usecs: 646.000, spare = 4687.000 load = 12.2936 max usecs: 673.000, spare = 4660.000 load = 12.2128 max usecs: 647.000, spare = 4686.000 delay of 6203.000 usecs exceeds estimated spare time of 4686.000; restart ... 23:11:13.187 XRUN callback (5). load = 12.2755 max usecs: 658.000, spare = 4675.000 load = 12.1850 max usecs: 645.000, spare = 4688.000 load = 12.3273 max usecs: 665.000, spare = 4668.000 load = 12.1640 max usecs: 640.000, spare = 4693.000 load = 11.9792 max usecs: 629.000, spare = 4704.000 load = 11.7837 max usecs: 618.000, spare = 4715.000 load = 11.8641 max usecs: 637.000, spare = 4696.000 load = 12.0824 max usecs: 656.000, spare = 4677.000 load = 12.1260 max usecs: 649.000, spare = 4684.000 load = 12.5321 max usecs: 690.000, spare = 4643.000 load = 12.4915 max usecs: 664.000, spare = 4669.000 load = 12.4899 max usecs: 666.000, spare = 4667.000 delay of 5249.000 usecs exceeds estimated spare time of 4667.000; restart ... 23:11:25.203 XRUN callback (6). load = 12.1516 max usecs: 630.000, spare = 4703.000 load = 11.8511 max usecs: 616.000, spare = 4717.000 load = 11.6165 max usecs: 607.000, spare = 4726.000 load = 11.6868 max usecs: 627.000, spare = 4706.000 load = 12.0031 max usecs: 657.000, spare = 4676.000