In recent discussions with my brother - professional photographer // camera repair services, I learned about a known issue regarding a loose screw inside Canon Rebel XT and XTi models.

My brother was looking for a used Canon Rebel XT (350d). We had one we were willing to sell to him... and did so. When he got it he noticed a little rattling noise when rotating the camera around. It sounded like one of those "tiny eye glass frame hinges screws" found in rolling around inside the camera body. Turns out nearly ALL the screws inside the Rebel Cameras are well seated.. then a tiny drop of glue is placed on the screw head EXCEPT the screw in the lower right back board.... which roams freely AND can short out the backlight orange wire and flame/scorch the flex.

IF you have a Canon Rebel and when tilt roll the camera around and you hear a tiny 'something' rolling around inside - STOP Turn the camera OFF and try to get the camera repaired under warranty as a manufacturers workmanship issue. OR risk the camera shorting out - total loss.

My brother uses a tech support forum.. today he is asking about 'Floating Screw' on other Canon camera models.