Blank page on load, and update -Wordpress

Hello :
I have been dragging this for a while.
Using the latest plugin (3.63) (and before) on wordpress, everytime I create a new post and access by default to the CKEditor, I get a BLANK area where I am supposed to type in the post.
If I click on the HTML tab and back to VISUAL tab, then, after a few seconds, I have access to the full functions of the editor.
Then, when I UPDATE, my post, the CKEditor fonctions dissapear, and I must click on thee HTML tab again and then the VISUAL tab, to refresh the area and gain access again to my content...

Any idea?