It's great to say my issues with the 7D are resolved now.
Canon customer relations asked me to ship my camera to their engineering department for evaluation since the repair center couldn't fix it after 4 tries .
Today I received a brand new 7D from Canon customer relations and it seems to work flawlessly.
When I shipped my old 7D to back to Canon, I had only shipped the body and kept the accessories just like when I sent it to the repair center. Customer relations sent me a full 7D kit with all of the accessories. And she told me I don't have to send my old accessories back and just to keep them. So I now have 2 batteries, straps, cables, etc..