In my case it seems to be a DMA related kernel BUG. Both usb and sound are on DMA 11, and my laptop has 3 different usb controller: only 1 (the one on DMA 11) is affected.
-- Sound from ES1978 Maestro 2E garbled when USB CD-ROM drive plugged in https://launchpad.net/bugs/21057 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
