It doesn't have to be; what matters is that's it being scheduled into a space that fragments the bandwidth the audio device needs. Even if the audio device only needs 3% of the bandwidth and the mouse .0001%, the mouse drops that USB frame into low-speed compat mode and blocks all higher speed devices from using any bandwidth during that timing period. If the audio device requires a tiny, uninterrupted piece of scheduling every period, it's just lost any chance of successful scheduling. On top of this, the Linux host schedulers are not particularly effective about avoiding these conflicts. [sorry for some ambiguity above; I don't remember if 1.0/1.1 drops a full frame to low speed or just the microframe]. Monty On Tue, Dec 10, 2013 at 8:28 PM, Bob van der Poel <bob@xxxxxxxxxxxx> wrote: > On Tue, Dec 10, 2013 at 6:04 PM, Gabriel M. Beddingfield > <gabrbedd@xxxxxxxxx> wrote: >> On 12/10/2013 02:12 PM, Bob van der Poel wrote: >>> >>> Figured it out after a few hours :) We'd only recently plugged her >>> mouse into the same multiport. If the "telephone" is plugged into a >>> different port, it works. If the mouse is not plugged into the >>> multiport, it works. >> >> >> Yeah, that's one of the hidden pull-your-hair-out gotchas of USB Audio. I >> ran into it once where an audio device was on the same hub as a webcam -- >> and that didn't work well. >> >> The deal is that the audio device reserves a certain amount of bandwidth >> over USB. If it can't get -- it won't even try to work. So if some other >> device has reserved the bandwidth you need (which they can), then there's no >> room left over for yours. >> >> -gabe > > Makes sense. But all that's on the port is a mouse and the telephone. > I don't see either one using much bandwidth. She uses the same port to > read pics from a camera, but that was not plugged. And, I rebooted to > make sure things were cleared out. Guess I've got a greedy mouse :) > > > -- > **** Listen to my FREE CD at http://www.mellowood.ca/music/cedars **** > Bob van der Poel ** Wynndel, British Columbia, CANADA ** > EMAIL: bob@xxxxxxxxxxxx > WWW: http://www.mellowood.ca > _______________________________________________ > Linux-audio-user mailing list > Linux-audio-user@xxxxxxxxxxxxxxxxxxxx > http://lists.linuxaudio.org/listinfo/linux-audio-user _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
