I know this is an *old* thread, but this came up when I was searching for Nite Rider issues. My NR Digital Evolution is doing the same exact things as the OPs light. My light is 3-4 years old and it started doing it this year. If the OP is still around, did you ever resolve it, or did you just use it and keep it charged up?
I haven't tried NR customer service yet but several people have mentioned that they want $$ just to look at the light. Since my light seemed to be working ok, except for the wonky fuel gauge I was just going to do as the OP was suggested: keep it charged and keep using it.
After this light is done I will buy another brand though.
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