When strip.show() is called a random LED blinks very quickly. I have tried using the FastLED libray and that does the some thing with the equivalent show command.
I am using a 12 LED ring with a 1K resistor on the data line.
The power to the LED ring is off a separate 5v source and has a 1000uF capacitor across the 5 volt input and ground.
No, it's connected to a separate power supply i.e. the Arduino is powered through the computer USB and the LED ring from a USB charger plugged into a powerboard. The computer and USB charger are on the same circuit.