Note: for this to work, both your PC and audio system must be equipped with optical ports.
How to Enable Optical (S/PDIF) Audio on PC
First of all, there’s the obvious matter of making sure that both your speakers and your PC have an optical (S/PDIF) port. With that off the list, simply plug your PC into your speakers using an optical cable. Note: if you’re using a full-blown audio setup that includes an amplifier instead of a standalone speaker setup, double-check the optical connection you’re using. Your system might offer different ports for optical-IN and optical-OUT. You want to connect your PC’s output to your speaker’s input. As with any cable format, companies will try to claim that their cable is better than others due to gold plating, “High Quality,” or other marketing jargon, but ignore all that. Buying a cheap optical cable should be absolutely fine unless you plan to tie it up in knots. Optical cables work in a similar way to HDMI in that they send digital signals that aren’t really subject to degradation. The main difference is that audio data uses less bandwidth than HDMI, so even if the quality of a cable isn’t great, you’re not likely to be affected. Once the optical cable is plugged in, click the speaker icon at the bottom-right corner of your Windows taskbar, then click the speaker name above the volume slider to see if an “Optical” or “Digital” sound output has shown up. If it has, just click to enable it. If the speaker doesn’t show up there, then right-click the speaker icon in the taskbar, click Sounds, and then the Playback tab. Right-click anywhere in the Playback tab list, then click “Show Disabled Devices.” At this point, a device called something like “digital output” or “optical output” should show up. Right-click it and click “Enable” to switch it on. Once you’ve done that, right-click it again and click “Set as default device.” You should now have optical audio enabled.
How to Enable Optical 5.1 Surround Sound on PC
Analog sound might still be okay for typical stereo setups. Still, when you enter 5.1 territory and modern sound formats like DTS, you just need a digital connection. If you don’t have one, audio decoding happens on your PC instead of your audio setup’s specialized hardware. The audio is then transferred there as lower-quality analog. Getting the connection to work may not be the most straightforward affair. Still, you should prefer using a standalone optical connection for your audio instead of an HDMI port. HDMI audio might be somewhat easier to set up but comes with significant limitations. HDMI has limited bandwidth and is used primarily for transferring video. Are you transferring high-rate video or playing games at ultra-high resolutions and over 60fps? Your HDMI might not have enough bandwidth to also transfer uncompressed 5.1 digital audio to your speakers. By using two dedicated cables for video and audio, you’re offering each their own pathway to your audiovisual setup for the best possible results. However, there are some caveats. First of all, is your motherboard capable of outputting 5.1 surround sound? Just because there’s an optical out port doesn’t guarantee that you’ll get surround sound across all your games, movies and so on. Your optical port on your motherboard should support 5.1 sound, though this will vary greatly depending on which Windows version you’re on, whether it registers as a Dolby-compatible output, and so on. You can check to see if your setup supports one of the Dolby 5.1 formats by going to the Sound window -> Playback. Right-click your device, click Properties, then the Advanced tab. Simply click the drop-down menu, select “DTS Interactive” or whichever 5.1 surround setup you want to use, then click OK. (If your PC doesn’t detect Dolby Digital, then you may have some work to do, and we’ve offered links to some workarounds in the conclusion.) You should also click the “Supported Formats” tab to make sure that the formats your receiver is capable of handling are ticked.
Check your App’s Settings
In some cases, you may find that although you’ve done everything correctly, you may not hear sound from some apps on your speakers. Some may do something that seems stranger, entirely ignore your multi-speaker setup, and only play audio from the front left and right speakers. When that happens, it’s time to look into your app’s settings. Each piece of software on Windows can sidestep the default audio setting. Your media player of choice may have “locked” on your analog output and not caught on to the system-wide change you made to your new digital-out connection. On a similar note, apps like Kodi offer options for managing your audio output. Through those, you can usually change the audio output device, encoding, number of channels, etc. When some pieces of audio only play in stereo, you can find the solution on either your standalone speakers, your amplifier, or your PC’s audio software. By default, multi-speaker setups play stereo streams from only two speakers since that’s the way the audio “was meant to be.” It was recorded in stereo, so it plays in stereo, using only two speakers. To have stereo two-channel audio play from all speakers, you should look for any options that look like “Stereo Expansion,” “Channel Redirection,” or into any “Surround Effects” available.
Conclusion
That should give you the basics of using an optical cable on Windows 10. The thing is, there is much nuance to it and many variables where things could go wrong. It’s not just your sound card and speakers that need to support it – it’s also the individual media you’re using, as well as the fact that recent Windows versions have made optical out support rather buggy. (You can no longer use the “Configure” button in the Sound window, for example, to enable 5.1 speakers.)
