I have the coax DSP carver system. Is it true that the coax only comes from the CD changer and the head unit uses normal wiring to the amp? I’ve heard this coax interface is SPDIF and Conversion is 16 bit 48kHz. Can I just buy an analog-to-spdif adapter? I found some that are only $15. If this will work, can I use a bluetooth to spdif adapter? These are about $20-$30.