Hi Jason. I get hum/buzz/hiss that is quite loud plugging either an SB2 or an SB3 directly into Nuforce Ref 8 amps. The noise goes away if I use a P8 or Plinius M8 preamp in between. The noise is there regardless of changing cables or power supply to the SB. The noise is louder on the right channel than the left. If I change things around channel-wise the noise is always louder on the right than left. There is way more other gear and cables close to the right than the left, which is presumably why that channel is always louder. While connecting one SB to the Nuforces, and plugging a second SB into the power the noise increases provided there is an interconnect connected to the second SB and it does not matter much whether the other end is connected to anything or not. Lastly I live in a place where we use 230V supply.