This is probably a CRT problem, caused by shipping damage.

My first Toshiba CZ 3299K suffered from really weird distortions, not unlike
yours. A reviewer had similar problems with his sample of this set. Toshiba
took my set back and refunded the purchase price, but the unit was bisected
by a fork lift at Toshiba, and no one ever figured out what the problem was.

I hope someone here has the right answer. If not, put the set in the back of
a pickup truck and run it over rough roads. (Seriously.) It couldn't hurt!