- Double-check all wiring. Are the green and yellow wires swapped? Is ground connected to the Arduino?
- Confirm that the Arduino is connected to the input end of the strand.
- Check power supply polarity and voltage. Are + and – swapped? If you have a multimeter, confirm 5V DC output (±10%) from the power supply.
- Are the power wires at the opposite end of the strand insulated or trimmed? They should not be left exposed where they might make contact with metal, or each other.
- Is the correct board type selected in the Arduino Tools→Board menu?
- Double-check all wiring. Are the green and yellow wires swapped? Is ground connected to the Arduino?
- Confirm the Arduino is connected to the input end of the strand.
- Is the correct board type selected in the Arduino Tools→Board menu?
- Did the LEDstream code successfully compile and upload?
- Inside each pixel there’s a small circuit board. Give the first bad pixel (and the one immediately before it) a firm squeeze where the ribbon cable joins the board — it may simply be a dodgy connection. If that works, you can either cut out the offending pixel and join the two sub-strands, or arrange for a replacement strand if new.
Some programs will have a “software renderer” option that may help. Or try running in windowed mode (rather than full-screen).
Sounds like you may have uploaded the LEDstream_LPD8806 sketch to the Arduino board instead of the regular LEDstream. For the Adalight Project Pack, or custom builds using similar WS2801 LEDs, you want the latter sketch, LEDstream. The LEDstream_LPD8806 sketch is only for custom builds using a different type of LED strip.
Computers will make our lives easier!