usb-audio: increate default buffer size

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

hw/usb/dev-audio.c

@@ -664,7 +664,7 @@ static const VMStateDescription vmstate_usb_audio = {
 static Property usb_audio_properties[] = {
     DEFINE_PROP_UINT32("debug", USBAudioState, debug, 0),
     DEFINE_PROP_UINT32("buffer", USBAudioState, buffer,
-                       8 * USBAUDIO_PACKET_SIZE),
+                       32 * USBAUDIO_PACKET_SIZE),
     DEFINE_PROP_END_OF_LIST(),
 };