dCS Network Bridge! I had NWB + Paganini DAC, a great combination. Replaced them with a Bartok. Quite similar in sound, actually. Maybe the NWB + Paganini had a little more air and refinement on the top end and Bartok a little more density and anchored sound. In the end it was more about the single box package and nicer looks rather than SQ upgrade. NWB comes up every month or two on the used market at < $4k. You can also potentially get rid of the Paganini clock as the NWB can also serve as word clock for the Paganini DAC, just have to see if the dedicated clock provides enough improvement, if any, to justify it.
Tried Lumin X1, both as streamer/DAC and just streamer into the Paganini, but found the NWB to be more natural sounding and dynamic.