Couloured spots on screen

If your model is a KDF-42WE655 Then it is LCD based rear projection TV .It cannot be affected by magnetic fields . Your colored spots are likely dust that has accumulated on the 3 lcd panels inside your TV (makes faint colored spots about the size of a half dollar ) OR failing polarization filter/lcd panel (very common in the blue panel(makes blue spots or yellow picture)).
The problem will be deep inside the very fragile optical block and I would reccomend contacting a local SONY servicer for diagnosis.

Hi
sounds like you have colour impurity problems caused by a magnetic feild being near the Screen. Fist check for any new magnetic feilds nearby. If there have been no new changes, it may also be a faulty PTC device that automatically degausses the tube. When they fail, you will get problems with impurities by way of coloured spots on the screen.
Try disconnecting the set off at the wall for 30 mins, this will initiates the auto degauss process. If all is ok, the spots will be gone. If not, you will need to have someone handy with a soldering iron that is also familiar with TV repair to replace the PTC for you.

Please rate this solution. Happy to answer any other questions you may have. Cheers.
regards robotek