Alexa I may just have found your answer.....maybe!

[Truffle & Podge]

http://www.youtube.com/watch?v=7sJSwKe5Ev8

Apparently they are called milk spots this vid gives 3 removal options, I tried the eraser one and it seems to have worked

Tasha X

[Alexa]

Thanks for great info Tasha! I suspect it's not this problem but will try eraser as soon as I buy one He said is mostly for "baked in" borax which is not a case here.

[Truffle & Podge]

The way he said it was it could be that but they aren't really sure exactly what causes it, so one of the three might work worth a shot, if it works then abracadabra lol X