I don't think the x3 supports surround sound on the ps5
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Also, the PS5 has no dedicated audio ports.
Supposedly you need a UAC1 device to get surround on the PS5. If you get a compatible device, you might be able to use the PC-Audio input which should be the green jack on the monitor as your front speakers and the 2.1 speakers as your side speakers. You'd need a 3.5mm cable for the monitor and may or may not need to use the displayport or DVI to prevent the audio defaulting to HDMI.