I got orange juice into my iPhone....Help!

Hi. I managed to knock a glass of orange juice over my iPhone the other night and now I can hardly hear calls. I didn't realise until morning so it had dried in before I could do anything. Everything else is working fine. I'm wondering if there is dried orange juice blocking the fine mesh that covers the ear speaker. Should I clean it with a damp cotton bud? Should I use water or alcohol? Any help greatly appreciated. Max