Recalbox v6.0 Dragonblaze

I've connected a Dell2007FPB to my Raspberry Pi 3b+ using an HDMI to DVI cable.

I've connected speakers to the 3.5mm headphone jack of my Pi. I get sound on startup of the splash screen on Recalbox, but get no sound during the games or on the main menu.
I've read loads of forum posts and scoured the internet. I've forced sound to the headphone jack but this still doesn't help.

Any tips would be gratefully received.
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