You will need to get that into the Switcher by embedding it.. This can be done with the RAVE Analog and AES audio breakout or another SDI Audio Embedder.
So the options are going to be based on how you want the audio to get out of the PC.. Also if you want multiple channels for multiple applications from the single PC there might also be a good option to use something like the Sonifex Dante to SDI embedder..
https://www.sonifex.co.uk/avn/avn-dio10.shtml
Then on the PC you can use the Dante Virtual Sound Card and have 8 x 2ch "sound cards" that would allow you in those applications to output to individual discrete "devices" that you could then embed into a video stream that is going into the switcher.
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Les O'Reilly
Director - Switcher Product Management
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