I purchased my C658 this week and love it. I primarily purchased it to stream Tidal HiFi (including MQA). Out of the box it sounded just ok, but I've left it on for several days now and it sounds better every day. Streaming Tidal sounds better than CD. I'm also trying out the internal phono pre-amp versus my internal PrimaLuna phono stage. At this point it certainly isn't obviously inferior or superior.I set up the DIRAC Live today. I wouldn't say this is a game changer at this point, but I haven't tinkered with the optimized equalization that the software develops. At this point the DIRAC derived sound is tighter in the low end, smoother, and slightly subdued. The BluOS app seems solid.I hope this helps