Sony rear projection CRT. Starts up for a few seconds and then the picture begins shaking while the picture stretches. If it is left off for awhile to cool down, it seems to go away.

Bad CRTs? Power Supply?

Here's what will narrow it down for you:

-post the model number and if the shaking stretching is in the H or V direction or both.
-post in the right forum
-it's not the tubes.