I recently installed hornby surface mounted points on my layout but have been having problems with them, i'm not sure if it is rm, the decoder or the points it is only on 2 sets going between lines but they don't seem to want to work together e.g. if one is curved the other is straight. sometimes it works for about a second and goes back, i have checked if they are getting jammed on ballast and they aren't, i have also changed the polarity on rm but it doesn't do anything.