You can configure Quicktime to be used with your 6.1 audi system.
- Open Quicktime
- Click on the Edit menu > Preferences > Quicktime Preferences
- Select the "Audio" Tab
- In the "Sound Out" section you'll have the opportunity to select the audio channel type.
- Click on the drop down menu and select "6.1 (L R C LFE Ls Rs Cs)"