I have 2 identical Bachmann HO EMD FT-A Diesel locomotives and I am trying to consist the 2 using a NCE Power CAB with Advance Consisting. It works fine with both locomotive pointing toward the same direction even with the rear programmed for reverse. When I place them back to back, they pull against each other? Does anyone have any suggestions on how they can be setup back to back and one is forward and the rear locomotive  is pulling backward? 

Yes, I heard the distorting sound before there was no sound. I sent it to be repaired.When it is returned I will lower the sound.

I just buy a Bachmann EMD SD40-2 w/DCC & Sound six days. Yesterday, the sound started to become intermitting meaning the sound would come on and off as it moved and the train then it would stop and not come back. The lights and the locomotive movement is fine.I am running an NCE Smart Booster SB5. Oh yes, I am knew to this. Help?