These cases warp with heat. I have never had the problem with my SB2-15, but my Original SB with power base scares me because it runs so hot. On one occasion recently I put it to sleep after a system update and walked away, returning later to find that it had tried to install Microsoft Office a second time, and it was just sitting there looping and cooking while it waited for me to provide an answer to a question I didn't know I had been asked. I cancelled the installation and turned the device completely off. When I went back an hour later, a straight edge showed that both the base and the clipboard had warped outer surfaces, and when I closed the Book, the upper part would contact the lower part only at the left front corner, leaving the right front corner elevated by about a millimeter. With some judicious thumb pressure I re-arced the upper edge of the clipboard and then bent the upper right corner enough in the other direction to make the device look straight when I closed it. I AM NOT ADVISING ANYBODY ELSE TO DO THIS. DO NOT TRY THIS AT HOME. I'm a risk taker, so I decided to try to make it look good again. I lucked out. This could have had some completely different outcome entirely.
But yeah, heat.
And the views without a response... Well, I am responding after my first viewing of your post. But I almost didn't. Who really feels a burning need to communicate with someone who uses a handle that is some variant on "Anon?"
Anyway, look at the activity levels for posts to the Surface forums on WinCen. This is one of the deadest sets of forums on the Internet. If you want fast replies, try Reddit.