Bitmap dissappears from stage

I have been noticing some wonky things going on when rendermode is set to GPU. I have a simple example(supports both portrait modes) where my assets are in a swc file. I add an asset(which is a bitmap) to the stage and use Tweenlite to move the object from point A to B. That works fine. What I happened to notice is that sometimes when I rotate my iphone 4, the asset will suddenly dissappear from the stage. Has anyone seen similar behavior and if so what have you done to resolve it?

Thanks!