I have Creative Inspire T6300 5.1 Speakers. I bought a new Analog to digital Converter - audio gear 5.1. My TV has an optical cable. How to connect the black / yellow and light green jacks to audio gear (analog to digital converter). I have an optical cable and optical audio out in the tv.
1. Set the TV audio output type to surround sound (might not be labeled clearly, if wrong you will get stereo).
2. Connect the TV optical audio out to Audio Gear 5.1
3. Connect the Audio Gear 5.1 to the inputs of the speakers with 3 cables with stereo mini plugs at both ends. Match the colors.
4. Turn the TV speakers off in the TV audio menu.
Since the TV output is fixed volume you would adjust volume with the speaker volume control.