I had a similar (but much less expensive) problem--anytime power went out and was restored to our home, then reading lights over our bed would turn on--even if they were off when the power failed.

I use an Ocelot controller for my X10 equipment, so I just programmed it to turn off everything that should be off when the power is restored. The reading lights still come on when the power is restored, but are now turned off by the Ocelot within about 2 seconds. Using the Ocelot, you should be able to accomplish what you want--either by using it to control an appliance module to turn the TV on and off, or by using an IR emitter to send a TV OFF code to turn the TV off (allowing it to keep power for memory, clock, etc). I'm sure there are other brands of controllers that would allow the same thing.