User Interface continually moving ('wigs out')


Hi there, my sister just got the A500 and it is exhibiting some bizarre behaviour. From her description:

well it seems to be behaving as though there is something moving the screen constantly, it kinda wigs out and brings up all kinds of different apps and the browser, etc. as though it's having a seizure. it's pretty annoying. then it kind of just freezes. but apps will work while it does that, which is strange. for instance, i was talking on skype and it would just bring things up and zoom in on them and out and in and out and in... and so on...

She is planning to take it back to the merchant, but I was wondering if anyone here had seen a similar problem.