If you're trying to play surround sound from your PC to your headset and you're only getting Pro Logic II (not Dolby Digital) make sure that trying to get Dolby Digital transmission from PC games. Most PC games use "multichannel LPCM" encoding for their soundtracks (Linear Pulse Code Modulation), not Dolby Digital encode/decode. Older (pre-2009) PC games do not include Dolby Digital Live processing to convert their LPCM audio to Dolby Digital inside the game, so only PCM (stereo) audio data will be sent through the PC sound card's S/PDIF Out (optical digital output).
DVD movie discs almost always include a Dolby Digital encoded soundtrack. You can try playing a DVD movie in your PC's DVD/CD drive, and choose the S/PDIF Out in the movie player software. That should send the Dolby Digital encoded audio data from the DVD disc, out through the sound card S/PDIF Out and on to the Headset's transmitter optical digital input. Your headset should then recognize the Dolby Digital encoded data stream and decode to 5.1 or 7.1.
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