http://bugs.winehq.org/show_bug.cgi?id=11764
--- Comment #16 from Raymond superquad.vortex2@gmail.com 2011-01-03 06:53:08 CST --- http://www.intel.com/support/motherboards/desktop/sb/cs-020642.htm
Those are motherboard with only 3 audio jacks at rear panel
Take a look at videos
For example, you can listen to one audio source through the back panel speakers and a second audio source through front panel headphones or speakers.