Mistake to change from Spectrum (Coaxial) to Fios (Fiber optical)???

I don't about burnin. I have Fios to a Verizon router to Bluesound Node2i and sound is superb.

Have you called Verizon?

Maybe there are settings for your router that Verizon tech support would know. Just a guess.

I do not have FIOS. Can you log into the modem? Try switching to PCM if Auto is selected in the audio settings.

Auralic is just a streamer? You have external DAC?

Potentially some incompatibility between the Auralic and your what I assume is your new Modem/Router?  If a new Modem/Router, since you have it hard wired, and throw in a DAC there, there could be some electrical issue and that seems more likely.

When you have digital streaming issues, you have drop-outs. You don't lose bass and you shouldn't have sound-stage issues unless your Auralic is doing something strange. 

Do a speed test so you know if you are as fast as your prior connection is. When I went from 25mbs ATT DSL to 300 mbs ATT fiber, sound got better. When I move to 1 gbs ATT fiber sound improved a bit more for sure. I have no experience with Spectrum. But I can say that moving from DSL over a telephone wire to fiber is better. In my area, you get much more speed for your money versus Spectrum.