ODP, white spots on leaves are either Thrips or Mites. I'm not sure about the Thrips but I have white mites myself, just found out tonight. Neem Oil, Mite X & Floramite are 3 good remedies, the thing is you have to treat every 7 to 10 days to kill the hatching eggs, and it's a good idea to use something different every time since mites build up immunities very quickly. I'd treat at least 3 times, 7 days between treatments just to be safe.
Hope that helps.