Solo streamer

Why not use the Cambridge with a stand alone DAC?   If you like the Cambridge user interface and are looking to improve sound quality , that's where I would start.  

You may want to consider the iFi streamer. It is an excellent and very inexpensive streamer that punches way above its very low price point. 

I have 2 Cambridge units. OneI use as a transport into my external DAC, a Bryston DAC3. The other sits in a midfi system and I use the internal DAC.

Obviously I ‘m a CA fan, and @oddiofyi suggestion is the way I would go,.  OP has stated in the past that enjoys his CA streamer, so I’m not sure why he has now become dissatisfied , but if he is using the internal DAC I think he should notice an improvement with using a better external DAC

@rvpiano

I’m very happy with my Aurender N200. There’s no internal storage unless you add it. No upsampling. Has critical listening mode that turns off non essential features including screen. Solid performer. Optimized for USB interface. 

@dickieboy. +1