Ah. That makes it a little more complicated, of course. Otherwise, I‘d have suggested getting an old second hand 5.1 audio receiver with S/PDIF input and using your TVs digital output (or an HDMI audio extractor if it doesn’t have one) to get the signal to your speakers. Receivers like that are usually very cheap. I’ve seen them go for less than 10€ in perfectly working condition.

But good that there’s a solution to get DV working. The Linux community never seizes to amaze me. Good luck implementing it.