Audioquest Niagara system with appropriately matched power cords did it here. Another step you can take is use sheet copper to maintain a barrier between analogue and digital components. In my case I use copper sheeting under my pre-amp and FM tuner. Streamer is directly below the tuner and my Benchmark DAC is right below the pre-amp. I also use Pearl tube coolers and solder a wire I can take to ground to them to drain off any RFI or EMI that may effect tube performance + the cooler has the tube’s head running 20 - 25 degrees cooler for longer life.
