4870 HDMI audio only in stereo

InterClaw

Junior Member
Mar 2, 2008
6
0
66
When outputting sound through my 4870 I only get 2ch stereo sound, even though I'm playing 5.1 sound (at least I think I am).

Here is an example:

Standard DVD with 5.1 audio
WMP11
Vista 64-bit, fully updated including sound and graphics drivers
X-fi (irrelevant, right? not used for this device huh?)
HD 4870 1GB + included HDMI adapter
High quality HDMI cable
Yamaha YSP-4000

The YSP only shows two channels and when configuring the speakers of the "Digital Output Device (HDMI)" I can only select "Stereo" (whereas on my standard X-fi speaker device I have multiple options up to 7.1).

What am I doing wrong here? My goal is to be able to play DVD:s and .avi:s with AC3 encoded sound through software players like WMP and VLC and get 5.1 sound in the YSP over the HDMI cable from the 4870.