It will spread if something is wrong. Can you make sure you have a 220 R resistor and that the voltage is 5V.
You need to subtract the forward voltage of the LED. Being white it might be as much as 3V so with that resistor you would get (5-3)/220 = 9mA. That should be well withing the limits of an LED, unless they are faulty or as I said the resistor or voltage is wrong, measure both with your meter.
The power supply is definitely 5 volts. I have measured it several times, and just did again. Maybe it's the source of the LEDs? I got them from a seller on eBay by the name of "Bright Components".
I seem to have blown the fuse on my multi-meter for low amp current readings, I will grab a fuse in the next day or two an update with an actual current reading.
Ahh, I originally stopped at the picture that mentioned "The RGB LEDs are a WS2812B strip".
Note: Just to mention - some types of paint could be conductive or semi-conductive (however I don't think this is the issue).
Careful there are no shorts (it appears some resistors could be shorting out).
It truly appears that the resistance code is red/red/black with black (multiplier) and brown (tolerance). If so, then these are 22Ω resistors and the excessive current will cause the LEDs to fail.
The first 3 colors should be red/red/brown for 220Ω. EDIT: (I see Grumpy_Mike is a bit quicker than I)
It is a 5 band resistor. Red + Red + Black + Black is 2-2-0 x 1 with tolerance on the end. I just measured too with my multi-meter, and they are inded 200ohm resistors. I think if you were right, they would have blown immediately, no? That would have been a lot of extra current with only 22Ohms.
For my own curious mind, would the following work. The LEDs are broken into 4 compartments regarding them sharing a positive power rail (all anodes connected), and I have a wire (4 wires total) that connect each of these sets to the positive power from the supply. Rather than changing out all the resistors, if I wanted to add lets say 50 ohms to all the leds, could I add a 50 0hm resistor to each of the wires so that way the resistance for each led would be effectively 270 ohms? I only have 1/4W resistors, so I am not sure if that would be too much load on the resistor.