On 07/27/2016 10:04 PM, Stefan Sauer wrote: > Hi, > > I own a Roland Gaia SH-01 synthesizer which has a USB interface to > connect it to a computer. Over this connection it provides both midi and > usb-audio. That is you can send and receive midi, but also audio. The > audio you play from the computer gets mixed into the audio you play on > the keyboard, but also the audio you play on the computer can be > recorded on the computer. For details, see pdfs: > http://roland.com/support/article/?q=manuals&p=SH-01 -> page 42 > > So far the theory. Attached is the alsa-info.sh output: > - all the devices are detected. > - midi-io works > - playing audio from the computer to the synthesizer works > - recording audio from the synthesizer does not, it records only silence > - alsamixer shows only one single control to set the 'midi input mode' > (whatever that is), there are not volume or mute controls for the audio > interface > > Another weir issue is that once the usb connection is established, > playing the synth from its own knobs and keys is super sluggish (e.g. a > key release is recognized with a multi-second delay). Playing it via > midi is okay though. > > The attached alsa-info.txt is from an ubuntu-14.04 machine. I've also > tested it against opensuse-13.2 with exactly the same issues. > > One detail is that when connecting the synth to usb I get several > "[159320.243035] usb 4-1.5: Unable to change format on ep #84: already > in use" messages in syslog. I have no idea what it means though (what is > ep #84???, in use by whom, ...). > > Any ideas what is going on here or how I can get more details? Is there > a way to trace usb activity on the specific device? I don't mind if it > gets a bit hard-core, I am a developer (mostly user-space though). > > Thanks, > Stefan A small update. When running aseqdump and connecting the Roland SH-01'd midi to aseqdump the sluggishness is gone. I can play it normally on the hardware too. Also I was searching for the usb error and I lead me to this thread: https://www.mail-archive.com/alsa-user@xxxxxxxxxxxxxxxxxxxxx/msg30331.html related to a device called "Boss ME-80" that has exactly the same issue. The thread did not got resolved. I also did usb captures with wireshark. lsusb shows "Bus 004 Device 007: ID 0582:0111 Roland Corp. GAIA SH-01" hence I capture from usbmon4. If I also start arecord in parallel I get data packets, but understanding them, is beyond me at this point. Finally, let me link to this ubuntu launchpad bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/902497 (with links to the git commits that added support for the synth). http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/?id=ae7cc709f2ec11b49fc31b20cd8c943794ae9576 if I look at HEAD, http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/sound/usb/quirks-table.h, this quirks entry seems to be gone? Am I looking at the right repo? Stefan ------------------------------------------------------------------------------ _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
