Can anyone help please. I have a new (1 year old) Bachmann class 40 D211 with sound. From being a really good runner straight out of the box it has started to run very erratically, sound breaking up , jerky running and even stopping. This has been a slow deteriation and the model has not had a lot of time on the rails. I don't want to return it as it is probably out of warrenty anyway. Did I read somewere that there was an initial problem with this model with an easy fix? If so I would be very greatfull for any help.