Innuos Zen to Stax SRM-D50 connection?

[AndrewStax]

I use an Innuos Zen mk1 music server. I've just ordered a Stax SRM-D50 DAC/energizer (plus headphones) and realise I don't quite know how to connect them. I currently link the Zen to a Naim Superuniti with Meicord Opal ethernet cable, one 7.5m length to a switch, then 2m to the Naim. The Stax DAC only has USB B, optical and coaxial digital inputs, no ethernet input. What's the best way to connect the Zen to the Stax DAC? Apologies if there's an obvious answer, like just using a cheap ethernet/USB adapter from the switch. I'm hoping I don't need a 10m audiophile USB cable! Thanks