> in that case it should default to the highest common number of channels, 8. What if the stereo stream started first? From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Kim Therkelsen Sent: Monday, February 4, 2013 2:29 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: Msvad pcmex, audio channel mask Hi Rob, Thank you for the answer. I was afraid of that. It is important for me to perform the downmix myself. Is there a way to accomplish this by for instance making a LFX instead? I also find the behaviour suboptimal in some cases. An example of this is when connecting a PC to a surround receiver using HDMI, in that case you would want the surround receiver to decide if an upmix should be performed and perform it if needed. Ideally it should know if the audio material is stereo or true 7.1 surround material. Even though Windows would not upmix the stereo content to 7.1, the surround receiver would not know this as it receives 8 channels (6 containing silence). I realize that it becomes a problem when playing back multiple audio tracks (both stereo and 7.1) at the same time on a PC but in that case it should default to the highest common number of channels, 8. Regards, /Kim