Just measured for spikes - there are some small ones on the 5v line lasting in the uS range. Largest I've seen was 0.341V. ADC line is dirty. I'm sampling for 20uS. I'll put a .1uF and a 1nF on there and see what happens.

I put a 10ms delay at the end of the flash subroutine and so far that looks to be working.