james_s, regarding comments on LED flicker:
Scope showing approx. 5 Usec. repeat periods, or about 233 khz, if the LED is using a buck converter (oscillator with inductor coil to boost voltage).
I get the 'dots' lingering visual effects, especially in side vision. But, the timing seems wrong, when reconciled with speed of (head) movement...the oscillator rate seems more like 3khz or something, a puzzle.
Do you have any info, on Manufacturer, model ?