Hello, I was told to email this to this list... I filed a kernel bug here: https://bugzilla.kernel.org/show_bug.cgi?id=90101 With the following content: "I have done extensive testing on this issue, and basically on any kernel version higher than or equal to 3.13, I am unable to use my USB Create Soundblaster card. The issue seems related to the USB subsystem as it works just fine in the USB3 ports. I did a kernel bisect between 3.12.0 and 3.13.0, and the offending commit is d0ce5c6b9208c79fc725c578eebdeb5724faf17d USB: EHCI: use a bandwidth-allocation table https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d0ce5c6b9208c79fc725c578eebdeb5724faf17d What happens is video playback stutters very heavily and there is no sound stream making it out the SPDIF port on the USB soundcard. I also tried with the speaker-test application and get a "Broken pipe" error. $ speaker-test -D iec958:CARD=Pro,DEV=0 -c 2 -t wav speaker-test 1.0.28 Playback device is iec958:CARD=Pro,DEV=0 Stream parameters are 48000Hz, S16_LE, 2 channels WAV file(s) Rate set to 48000Hz (requested 48000Hz) Buffer size range from 96 to 262144 Period size range from 48 to 131072 Using max buffer size 262144 Periods = 4 Unable to set hw params for playback: Broken pipe Setting of hwparams failed: Broken pipe If I move to the USB3 port it works as expected, so the issue is most definitely on the USB2 side. The USB hardware is: 00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04) Subsystem: Lenovo Device 3086 Kernel driver in use: ehci-pci The Soundblaster hardware is: Bus 001 Device 004: ID 041e:30df Creative Technology, Ltd" Thank you for your time. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
