Hi, I''d like to ask if anyone managed to get USB audio passthrough working? In order to minimize PCI passthrough usage (I get audio dropouts on PCI audio passthrough (Intel ICH audio) lasting 10-30 seconds every few minutes), I got a generic USB audio adapter. It works fine on bare metal but in domU all I get is loud crackling noise instead of sound. Could this be related to Xen USB passthrough being limited to USB 1.1 and the USB audio possibly requiring more bandwidth than that? Has anyone got USB audio passthrough working successfully and reliably? What USB sound module did you use? Gordan
On 02-06-13 11:06, Gordan Bobic wrote:> Hi, > > I''d like to ask if anyone managed to get USB audio passthrough working? > In order to minimize PCI passthrough usage (I get audio dropouts on PCI > audio passthrough (Intel ICH audio) lasting 10-30 seconds every few > minutes), I got a generic USB audio adapter. It works fine on bare metal > but in domU all I get is loud crackling noise instead of sound. > > Could this be related to Xen USB passthrough being limited to USB 1.1 > and the USB audio possibly requiring more bandwidth than that? > > Has anyone got USB audio passthrough working successfully and reliably? > What USB sound module did you use? > > Gordan >Hi, I worked around a possibly similar problem with built-in Intel HD audio by initializing it on the dom0 (instead of hiding it) before doing the PCI passthrough. Also got some helpful advice over USB audio before, see thread: http://lists.xen.org/archives/html/xen-users/2013-05/msg00166.html I''m sorry that I cannot give you more specific help, as I have no experience with USB audio myself. Arjen
On 06/02/2013 10:29 AM, Arjen wrote:> On 02-06-13 11:06, Gordan Bobic wrote: >> Hi, >> >> I''d like to ask if anyone managed to get USB audio passthrough working? >> In order to minimize PCI passthrough usage (I get audio dropouts on PCI >> audio passthrough (Intel ICH audio) lasting 10-30 seconds every few >> minutes), I got a generic USB audio adapter. It works fine on bare metal >> but in domU all I get is loud crackling noise instead of sound. >> >> Could this be related to Xen USB passthrough being limited to USB 1.1 >> and the USB audio possibly requiring more bandwidth than that? >> >> Has anyone got USB audio passthrough working successfully and reliably? >> What USB sound module did you use? > > I worked around a possibly similar problem with built-in Intel HD audio > by initializing it on the dom0 (instead of hiding it) before doing the > PCI passthrough.The odd thing is that it works fine initially, then at random intervals every few minutes it will drop out completely and go silent, before returning and continuing to work fine. If it was an initialization issue I would have expected it to not work to begin with (or at all).> Also got some helpful advice over USB audio before, see thread: > http://lists.xen.org/archives/html/xen-users/2013-05/msg00166.htmlAs I said, I do have a generic (£3) USB audio adapter that works fine on bare metal on 3 different machines, but when use with my domU, all I get is loud crackling instead of sound. The crackling stops when the audio playback stops, so I''m wondering if it could be an issue to do with the device connecting as a USB 2.0 device to the host, but then being passed as a USB 1.1 to the domU; and if that is the case, whether there is a possible work-around. Gordan
Hi Gordan, On Sun, Jun 2, 2013 at 5:10 AM, Gordan Bobic <gordan@bobich.net> wrote:> On 06/02/2013 10:29 AM, Arjen wrote: > >> On 02-06-13 11:06, Gordan Bobic wrote: >> >>> Hi, >>> >>> I''d like to ask if anyone managed to get USB audio passthrough working? >>> In order to minimize PCI passthrough usage (I get audio dropouts on PCI >>> audio passthrough (Intel ICH audio) lasting 10-30 seconds every few >>> minutes), I got a generic USB audio adapter. It works fine on bare metal >>> but in domU all I get is loud crackling noise instead of sound. >>> >>> Could this be related to Xen USB passthrough being limited to USB 1.1 >>> and the USB audio possibly requiring more bandwidth than that? >>> >>> Has anyone got USB audio passthrough working successfully and reliably? >>> What USB sound module did you use? >>> >> >> I worked around a possibly similar problem with built-in Intel HD audio >> by initializing it on the dom0 (instead of hiding it) before doing the >> PCI passthrough. >> > > The odd thing is that it works fine initially, then at random intervals > every few minutes it will drop out completely and go silent, before > returning and continuing to work fine. If it was an initialization issue I > would have expected it to not work to begin with (or at all). > > > > > Also got some helpful advice over USB audio before, see thread: >> http://lists.xen.org/archives/**html/xen-users/2013-05/**msg00166.html<http://lists.xen.org/archives/html/xen-users/2013-05/msg00166.html> >> > > As I said, I do have a generic (£3) USB audio adapter that works fine on > bare metal on 3 different machines, but when use with my domU, all I get is > loud crackling instead of sound. The crackling stops when the audio > playback stops, so I''m wondering if it could be an issue to do with the > device connecting as a USB 2.0 device to the host, but then being passed as > a USB 1.1 to the domU; and if that is the case, whether there is a possible > work-around. > > Gordan >I ''cheated'' in that I just passed one of the USB controllers through to my windows domU, then use a pair of USB headphones that I switch from one port to another, depending on which VM i''m currently using. Not had any issues with it that way. Regards, David _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On 06/02/2013 03:05 PM, David Sutton wrote:> I ''cheated'' in that I just passed one of the USB controllers through to > my windows domU, then use a pair of USB headphones that I switch from > one port to another, depending on which VM i''m currently using. Not had > any issues with it that way.Yes, I was doing that for my keyboard and mouse passthrough to domU, but found that PCI passthrough on USB controllers was a bit hit-and-miss - they often wouldn''t come up properly when rebooting the VM. I switched to using USB passthrough because of that, and since my audio PCI passthough wasn''t entirely trouble-free, I thought I''d try the seemingly more stable USB passthrough for that purpose. Gordan
On Sun, Jun 2, 2013 at 10:17 AM, Gordan Bobic <gordan@bobich.net> wrote:> On 06/02/2013 03:05 PM, David Sutton wrote: > > I ''cheated'' in that I just passed one of the USB controllers through to >> my windows domU, then use a pair of USB headphones that I switch from >> one port to another, depending on which VM i''m currently using. Not had >> any issues with it that way. >> > > Yes, I was doing that for my keyboard and mouse passthrough to domU, but > found that PCI passthrough on USB controllers was a bit hit-and-miss - they > often wouldn''t come up properly when rebooting the VM. I switched to using > USB passthrough because of that, and since my audio PCI passthough wasn''t > entirely trouble-free, I thought I''d try the seemingly more stable USB > passthrough for that purpose. > > > Gordan >Hello Gordan, I haven''t tried USB passthrough on Xen yet, and I admit that I haven''t thought of trying, really, only because I''ve had such a poor experience with it in the past on ESXi. When I first undertook the task of getting audio output from my VM (along with Keyboard/Mouse input!) USB passthrough was my first idea... but it was just all crackly and terrible. I was using a quality device, too---a Sound Blaster X-Fi---I tried others, too, but that didn''t seem to matter. The next stop on getting this to work was instead to pass through a USB controller, but the board I was using didn''t play nice when I did that. The onboard USB2''s were all hung off the PCI bus, which meant ESXi wouldn''t let me pass them at all, and the USB3 controllers just flat out didn''t work. I tried a commercial USB-port sharing product called USB Redirector<http://www.incentivespro.com/usb-redirector.html>. It worked *very well* for both Audio and Inputs. No latency, no crackling.... but at about the cost of $40 per device... Since I needed twelve devices, I scrapped that idea. The USB/IP project shows promise, but at the time wasn''t far along enough for me to consider using it. I think that now, though, it might be worth investigating. If you want to work this out with software, I''d actually suggest looking into that the most! I''m admittedly a little puzzled by the fact that you''re having problems with PCI passthrough of a USB controller, especially because you have an Intel-based system... I always remember reports of that "just working." If you''ve got any more PCIe slots on your system, a USB3 add-in card might be the way to go... just make sure it doesn''t take power from a molex plug :P Best Regards, Andrew Bobulsky _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users