Sound Changes Automatically!

[Nickey]

On www.youtube.com
I watch a video and then I select another video!
The sound somehow automaticly changes to SPDIF Interface!
When ever it changes it will never send sounds to my speaker!

Question one =
How do i make it stop switching from Speakers to SPDIF Interface?

Question two =
Where happens to the sound when it is in the SPDIF Interface?

 

[fireberd]

You didn't fill out the system specs and that would help someone to help you.

The sound output ("Playback") can be set in Control Panel/Hardware and Sound/Sound Panel. In the Playback section you can select the "default playback device" which is normally your speakers.

On thought, are you watching through a Video card HDMI connection? On some Video cards, there must be a connection to the PC's S/PDIF connection for the HDMI audio.