I have allergies that mean that for most of the winter I have very nasty sinuses and frequent chest infections. I'm trying to work through this with my singing, but a big sticking point is always breathing. I think my basic technique is right. My ribs swing outwards, I open my mouth and throat. But because mouth, throat and sinuses are often not in great nick, there's often a sucking or whistling sound.

Does anyone have any ideas on how to work with this?