I've never used the ADAT output, but I have used the optical S/PDIF so that's why I pointed it out. In Scope, I had to select optical S/PDIF instead of ADAT to get sound, so I would imagine it was sending audio to ADAT otherwise. PLEASE ask someone here who might know better because my current plate, the PLUS Plate, the optical outputs are locked in ADAT. I wish I could select optical S/PDIF, but it won't let me do that. Even though in Scope I select between optical S/PDIF and ADAT I get no audio using it as an optical S/PDIF. That's no big deal for me, because the device I need to send audio to has AES/EBU so I just use that.