NAD C 658 DAC

Not certain that would want to purchase a product that lets something like the issue above get out the door. Looks like it’s Lumin for me

I think they're still working out software bugs, like most companies do with complex computer driven products these days (Apple for instance). I think it's a stellar unit. Really sounds amazing, and interface with the BluOS app is great. I don't regret buying it at all.

Dirac Live 2.x is now available for the NAD C658, personally I prefer using a Mac or PC for calibration but it can be done with a smartphone as well: https://youtu.be/I8uZ3tZc9mw 
:) Flavio

I bought an early unit several months before the Dirac update. As with some of the older OPPO players I knew the Sabre DAC would require some run in time. Before I ever listened to it I ran it 24 hours a day for 6 days. Didn't help. The digital glare was so excruciating even my wife noticed it. Out it went and taking its place is a TEAC NT-505. Worlds better. I will say the Bluesound app is superior to the one TEAC and Lumin use but the difference in sound is huge.

Man, the performance of NAD's digital devices is all over the place.