Not play to USB DAC

Hi,
Mopidy can play on my on-board sound card device, but when i set the alsa default to USB DAC, Mopdiy cannot play on it.
below is the warning i got.
2019-01-03 11:03:48,519 WARNING [1642:Audio-2] mopidy.audio.actor: Setting GStreamer state to GST_STATE_PLAYING failed

in mopidy.conf
i just set the audio/output to alsasink

what i am missing?
thanks!
Joseph

How are you doing that? Are you not selecting usb from the websettings audio section? You should not be hand editing anything in mopidy.conf.

What usb device are you using, exactly?

i didn’t install the websetting extension.
i set the default sound card in ALSA /etc/asound.conf, so mopidy should play to this default.
but seems gstreamer has problem with that …

is the mopidy->gstreamer->alsa->usb sound card ?

Joseph

Are you using Pi Musicbox? http://www.pimusicbox.com/

no, just mopidy.
i should ask in another discussion group.

I have also difficults with my raspberry and the usb. I connect a MusicalFidelity M6SDAC to USB. It is detected, but when I play music, the M6SDAC shows the right sample rate of the current song, but nothing is to hear.
I use musicbox_v0.7.0RC6. When I play music with my Linux-PC the behaviour is the same. When I play music with my Windows-PC the music plays (after installing a special usb driver). MusicalFidelity means that the M6SDAC should be detected with Linux kernel 2.6.33 or later. Can you please help me.