Hi all, I've been having a problem lately with two of my USB devices. I have a DVB-T USB adapter (to watch tv on my laptop) and a Native Instruments Audio4DJ USB sound card. Both devices work wonderfully when I come from a fresh boot (I can watch tv with the audio routed through the sound card). However, once I disconnected the audio card and reconnect again, I get this regular but not periodic interference on the audio card. By "regular and not periodic" I mean that the time elapsed between each interference is random, from 0.5 to 30 seconds, but it keeps happening. The interference is a kind of crack and pop which affects all output channels of the audio card. >From now on (until I fresh boot again), I can reconnect the audio card as many times as I want, rmmod and modprobe its module again and I always get the interference. Note that unplugging and plugging the DVB adapter makes no difference, and if I fresh boot, connect both devices, disconnect the DVB card and reconnect, I do not get interference - only when I do the same with the audio card. After much research I found the culprit - apparently if I rmmod and modprobe the ehci_usb device the interference is gone without having to fresh boot (of course before this I unload the modules for the dvb and audio devices). I was to able to reproduce this problem in kernels 2.6.31 to 2.6.33 (I haven't tried any others). I WAS NOT able to reproduce on a ICH4 laptop I have. The DVB-T adapter uses the dvb_usb_dib0700 module and the audio card uses the snd-usb-caiaq module. My laptop is a Lenovo T400. Attached are the lsusb and lspci -vvv. Please let me know if you need any more information. I'm mailing here for advice before I file a kernel bug, if you can help me anyway I would appreciate it very much. Thanks, Pedro
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lsusb
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lspci
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