Wrong number set in CV29. 34 is when you DON'T want the decoder to respond to a DC current on the rails. You want a value of 38 set into CV29.
Crandell
I have an Athearn SD60M with a QSI Titan decoder. It works beautifully in DCC. However, on the club's DC layout it sits there and produces sound when the DC controller is turned up, but it does not move at any speed setting. The CV 29 is set for 34 so it should work in DC and DCC. Is there some other setting that could be affecting this locomotive?