Inakustik Digital audio toslink to mini toslink cable
TOSLINK - Wikipedia
TEST: Google Chromecast Audio - recordere.dk
Mini-Toslink cable (5 meter)
What's in the box? - Chromecast Help
Amazon.com: Mini-TOSLINK Optical Audio Cable with Signal Protection – 20ft (Mini-TOSLINK to TOSLINK, Digital S/PDIF Cable/Fiber Optic Cable for soundbars, Stereo Systems/amps, Hi-Fi) by CableDirect : Home & Kitchen