I also have a new P2K GP-30 dcc and sound and it’s not the quietest engine that I own. It makes a little more of a buzzzz in reverse than in forward. I have one of the much vaulted Kato SD-40’s and even it has more of a hummmmm than I’d like. I sent a BLI 2-6-6-4 Class A steamer into BLI because I thought the noise in reverse was a little much and recieved it back with a note saying the noise level was in the ‘acceptable range’. The quietest engine I have is a P2K dcc and sound 0-8-0 switch engine. Not only is it beautifully detailed, it’s quiet as falling snow.
So…, I’m beginning to believe… with my limited experience… that if you set a new engine… right out of the box… on your track and it’s quiet as a mouse, you’ve gotten a little lucky. 'Course, it gets into what is ‘acceptable range’, doesn’t it. Let us know your progress on this one, I’m interested for sure.
JaRRell