Lightroom defaults

Hi Folks,

When my 5d Mark II photos first appear on the screen in Lightroom for "developing", the image looks about right for a quick second, and then the program adjusts the image - I assume to some default setting. Brightness 50, blacks 5, contrast 25, etc. The problem is that in many cases, the image was better before the default than after, and I wind up scrambling to try and recreate what I saw for a second. Way too much contrast, and too dark. Can anybody advise me how to make Lightroom leave the image alone until I make the change?

Thanks.