I'll look into it for the next iteration! I could just take the transcript that's already on the page and put it somewhere separate from the audio.
But thinking about it a little more, what would the use case for a text version actually look like? I feel like if you're already on HN, navigating somewhere else to get a TLDR would be too much friction. Or are we talking RSS/blog type delivery?
What about putting the text version that's used to make the audio somewhere on the page? (or better, on a subpage where there's no audio playback)