When looking at the suttaplex card you can see a button to SC voice:
But when actually reading the sutta, I don’t see a way to click a link to voice.
A similar card of info can be seen when clicking the parallels icon. But the button for voice is missing:
My personal experience is that considering voice should be broadening access to the suttas, it is very hard to access.
On the voice side of things, there is no traditional navigation at all (you either have to know the citation or you have to search a topic). So I feel stymied coming and going.