Mysterious black textures

Sometimes when building an iphone game some of the textures will appear solid black, it doesn’t matter what texture or material or shader is used. Also it seems to happen randomly as rebuilding the same project fixes it sometimes. This is a bit of a hassle and a huge time waster if you’re sending a binary or update for app review as you wont know if the game has this problem till it’s on the store and someone complains about it and then you have to wait a couple more days to get through review again.

I’ve seen this happen on other people’s games as well so it’s not just mine. It also happens on different models of iphone/ipod/ipad rather than all of them at the same time.

Has anyone else experienced this and what’s causing it?

I’m experiencing this too, but in my case, all the textures are black, not just some.

I’m on ipad, using unity3.

EDIT: I was wrong, it just seems to be the lightmapped objects…

I have the problem as well in android
Sometimes some sprites become black randomly!