If you have a older xbox 360 elite, you may have noticed that the HDMI output is only in 2.1 format. This is a quick fix, which you may have easily overlooked.
Step 1: Check Your Connection
Be sure your xbox is connected to your pre-amp with a HDMI cable or a optical cable.
Step 2: Toggle the Setting
Change from 5.1 to stereo and back again.
Step 3: Success!
You now have full 5.1 surround sound for your 360!
You may have to repeat this if it happens again.
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