I had a similar problem. The first time it took all of my strength to pull it out so I sat there and did it again a couple times to loosen it up. This worked a little, but not as much as I had hoped.
The trick I used was this Silicon-based Gun Lube i had lying around for my rifle. Since it is Silicon it won't mar Plastics, and it does not interfere with electronics.
So i sprayed a little on my finger and rubbed the tiniest amount on the sides where the camera slides into the mount and it worked like a charm. It goes in smoothly, backs out smoothly. When it was in there, it was very tight like before.
Your mileage may vary, so good luck. This is only my experience so i have to disclaim any involvement in damaging your electronics if you decide to do this yourself.
Thanks!