I have a brand new Audioquest Carbon digital coax cable. I don’t currently have nor have I used another external DAC with the Oppo. I have a Node hooked up to the Tambaqui via Optical and it works fine. I’ve programmed the Tambaqui input 3 for the spdif and selected that input.
Oppo Settings:
Playback - I’ve toggled between Multi-channel, Stereo and CD Mode for SACD priority
Audio Format Setup - Secondary Audio = off, HDMI Audio=LPCM, Coaxial/Optical Output= Bitstream ( I’ve toggled between 48k,96k, 192k LPCM and Bitstream for this). SACD Output = Auto ( toggled between PCM and DSD for this)