Hello Gene!
I am not familiar with the CM20, but my suspicion is that it is working in a " pulse" mode. Do you have any switches to turn off the pulse? Some of the H0 transformers from MRC will allow this.
This is my best guess.
Paul
I recently boguth a CM20 on Ebay. I use Bachmann Bog haulers sound PCs which I have made to work on track power.(Around the ceiling layout and I don't want to climb areound to turn off/change batteries. My problem, the sound works fine with my Aristocraft 5400S transformer, but when I change to the CM20 there is no sound unless it's at full throttle. MRC is stumped.
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