50D Problem

[ToogiiK]

Yester I went to the mountains and I had my camera on for like 3 hours, and when I came back to I heard something lose in the camera whenever I shake it. Can someone tell me if this a common problem or a major one. Also the pictures turn out good as usual. Also I see a white dead pixel looking thing on my screen when the cameras on and off, but the white dead pixel doesn't show in the pictures, can someone tell me how to fix it. Its just bothering me a lot.

[look_yau]

if the white pixel is not on the pictures, it must be either dust in the mirror or viewfinder.
the best way to deal with is to ignore it.

I have been though the same, it is bothering me a lot at first, but when time goes you know you should just spend more energy on getting good pictures intead of caring about the dust that will not even appears in the final result.