In my install I’m going to use my phone and the apple camera kit to go into this topping d10 and send optical/toslink straight to the helix and adjust vol through a urc.3 for now and eventually director or conductor, once i figure out the best place for it. I also have the helix wifi piece but rather have a physical knob for vol. At least that’s the plan for now.Well.. you get it figured out and let me know how firstI feel like the best source would be to keep the signal digital all the way to the digital signal processor. It's a shame that even the most expensive Pioneer HUs (not sure about other brands) still have no digital output. Could go straight from the phone but after a quick search there doesn't seem to be an obvious way to output an optical signal from an iPhone. Not even a USB to SPDIF/TOSLink adapter looks to be readily available.
If you get to the point where you feel like you tried everything, it could just be the software. I spent two days trying to get ANY sound from my Helix DSP. Someone suggested I try redoing the IO from scratch. I reset all settings and started on a fresh preset. Set IO and XOs same as before and then it worked.

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