For several years I have been using DCC decoders from Lenz or some locally made brand; both working pretty well. Recently I bought sound decoders (fromSountraxx). Sound is great, BUT pretty soon I found that they are very sensitive to dirt on the track: even the slightest dirt brings the engine to a stop and then restart (or stay idle if the dirt is larger). Things are worst with a long acceleration rate (CV 3). Am I the only one to notice that ?