There are two ways to fix the gaming PC without an audio problem because the audio has been transmitted to the streaming one.
The first one, you can connect the HDMI cable from the HDMI out port on the capture card to your gaming monitor if the monitor has a built-in speaker.
You could see the below example:
The second one, you could follow the below video:
If you want to play audio simultaneously through both your headset (Gaming PC) and the HDMI output (Streaming PC), please refer to this guide: http://d164vpkda9uyv1.cloudfront.net/web_upload/consumer/support/faq/VoicemeeterPro-EN.pdf
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