A problem that is common as Mitsubishi rear projection TVs begin to age is what is known as the "dead pixel." A dead pixel will take the form of a tiny, barely noticeable blue or black dot that never changes no matter what is on TV. Dead pixels are covered by Mitsubishi's manufacturer's warranty, though depending on when you purchased your TV and what model it is, they may require a certain number of dead pixels before going ahead with any kind of free service repair or replacement plan. More information on this can be found in your owner's manual.
If your television has begun to randomly shut itself off, it is more than likely due to the fact that it is overheating. Due to the nature of a Mitsubishi Rear Projection television, this can be common as your television ages. To prevent this, make sure the air vent on the back of the TV isn't pushed against the wall or covered by anything else. Also, make sure nothing that generates heat is near the television. If your TV is overheating, shut it off for a decent period of time (five to eight hours), giving it a chance to cool down before you attempt to use it again.
If, when watching television or a DVD or Blu-Ray, you notice that every person onscreen seems to have a jagged, almost static line around them, there are a few potential reasons for this. When DVDs first came onto the market, companies employed a technique called "edge enhancement" to attempt to make a softer picture seem sharper and more defined. It was generally abandoned, however, as when higher definition TVs came out, the consensus was that it made the picture look worse. If this is the case, there isn't really anything one can do about it. However, check your TV settings to make sure the "Sharpness" option isn't set to high. That will also cause these jagged lines.