tellybelly,
Try toggling between sending the audio stream either PCM or bitstream, depending on what signal your docking station can handle.
--HDTech
I have a Samsung UE32B6000 LED TV and the down firing speakers give out a pretty poor sound.Otherwise I love the TV though. I attached an optical cable with a jack converter and plugged it into my ipod docking station (which has its own power supply) but even when I select External Speakers in the audio settings it won't work at all.The red light is shining through the optical cable and jack so I assume it's live. Any suggestions out there?

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