Optical digital quiet?

[Nputcha]

S/PDIF (Coax, Toslink) full scale digital (0dBFS) should produce similar loudness to UPnP, but it is of course possible that the TV box has a fixed attenuation on the digital signal.

I asked devialet about this as I’d assume same and as I am debating between using optical or Dante audio-over-ip (what devialet pushes)  this is response, though I’ve asked for more clarification. Could be that they “map” volumes for line in differently to respect a broader range of input levels, or possibly the below means that line inputs will always be constrained vs wireless, though that seems unlikely. 

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I just spoke to my technical team. What I found out, is that it is normal for the volume on the phantom II to be lower on line in or optical as this is to protect the drivers. In other words, it is intended this way. They also shared it also depends on the cable as well. When you use Dante, you can control a lot of things via the Dante controller. Things such as audio quality , maximum bandwidth, volume etc. a lot of options. In short, highly customisable when using Dante.

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