> I'm confused how it negotiates with underlying alsa device? Does it > need some changes in alsa driver? E.g. I have an HDMI device, and I > would like to pass a dts-wav file directly down to this device. Are > there some commands like 'gst-launch filesrc location=test.wav ! > pulseaudiosink'? Just to be clear, there's no negotiation with the alsa device for now. I've been pushing for a kernel patch that makes the ELD information available to user-space, and I have some code to read it in pulseaudio. We now have to take the ELD information and set the formats automagically. For now as Arun said you have to set the formats by hand in PulseAudio so that they match the capabilities of your receiver. -Pierre