Grizz missing while holding steady throttle

[Rangerman97]

Ok so got out today and went riding and noticed a slight miss. Later discovered that it is way worse holding a steady throttle either in park or just cruising at low speeds (less than 10mph). While in park I can slowly push the throttle down and at about 1/4 throttle it starts missing bad. The optimizer lights go from green to red ever time it misses and the very last light flashes on and off. I put a new spark plug in it and cleaned the air filter trying to eliminate them as possibilities. Any help will be much appreciated.