yeah put the vial in a hot water bath... u guys remember ur chemistry right, solubility increases with temperature, heat it up, it'll go back into solution. Crashing out means it got too cold at one point... as soon as some crystals appear, they act as a seeding point for the rest of the compound to recrystallize at. Crystals are stable so they'll stay that way even at the same temp that they'd normally be dissolved at, need to heat it up to get them back in solution.