Comment # 3 on bug 1116225 from Takashi Iwai

Both TW and SLSE15 VMs showed the problem, so VM is likely irrelevant.

I tested the direct invocation with Gtk.

  qemu-system-x86_64 -machine accel=kvm -m 1024 -drive
file=tw.img,format=raw,if=none,id=hd,index=0,media=disk -device virtio-scsi-pci
-device scsi-hd,drive=hd -vga cirrus -net nic -net user,hostfwd=tcp::10022-:22
-soundhw hda -smp 4

It's running on a normal user on XFCE desktop without PulseAudio, and qemu can
certainly access to the audio device.

The problem happens with both dmix ("default") and the direct acess ("hw" or
"plughw") passed to QEMU_ALSA_DAC_DEV and QEMU_ALSA_ADC_DEV.

The audio with qemu worked fine in the past with the very setup and machine. 
It's been broken since some update, likely 3.0.