Mine occasionally sticks when I've got my iPhone 5 connected with a pretty long lead, I tend to give it a good pull open and it'll come free. I was a wee bit concerned I'd break it but I've had to do it two or three times and it seems to work fine still. I am pretty careful to make sure the phone and lead are well down at the bottom of the cubby hole, or leave it open when the phone's connected.
Give it a yank, what's the worst that can happen?
G