What tutorial did you follow? I added a resistor & capacitor in to get mine working. It is related to the signal drop due on the data line and the overall length of the wire run. The resistor is the key as it acts as a LED in the middle to. Some people put a sacrificial LED in the wire from the SLB instead. LED strip odd behavior Altmill/SLB-EXT - RING works, RAIL is white - #14 by whitewolf