Description of problem:
No sound can be heard when playing music in guest with ES1370 over spice, although the music or video can play without any error prompt.
But for VNC, this issue does not exist.
And for AC97 at the identical setup, AC97 can work correctly over spice. 

Version-Release number of selected component (if applicable):
kernel-2.6.32-220.el6.x86_64
qemu-kvm-0.12.1.2-2.209.el6.x86_64

How reproducible:
always


Steps to Reproduce:

1. Start rhel6.2 guest with ES1370 as following CLI:
 /usr/libexec/qemu-kvm -m 4G -smp 1 -cpu cpu64-rhel6,+x2apic -usbdevice tablet -drive file=rhel6.2.qcow2,format=qcow2,if=none,id=drive-ide0-0-0,werror=stop,rerror=stop,cache=none -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -netdev tap,id=hostnet0,script=/etc/qemu-ifup0 -device virtio-net-pci,netdev=hostnet0,mac=00:10:16:10:33:16,bus=pci.0,addr=0x4,id=virtio-net-pci0  -uuid 4dd75035-2cb9-46b5-a040-78223751601e -rtc base=localtime,clock=host,driftfix=slew -no-kvm-pit-reinjection -monitor stdio -name rhel6.2 -spice disable-ticketing,port=5930 -vga qxl -device ES1370,id=sound0,bus=pci.0

2. Play MP3 music or other video in guest
  
Actual results:
No sound can be heard when playing music in guest with ES1370 over spice, although the music or video can play without any error prompt.

Expected results:
Music should play correctly.

Additional info:
I have tried on xp / win2k8-64 /rhel6.2 /rhel6.2, all of them have the same issue with spice.