What about.. :) –
I agree with the earlier post, dialogue isn't always the best way, especially since you are coming out of the corner, and it seems to be a quicker scare.
I would toy with a few ideas...
Maybe make the sound of the tv, but loud and "juicy", then top off with a giggle, or insanely say"cable's out!"
Or get a remote and yell "CLICK" over and over - again insane (i LOVE insane obviously LOL)
"No tv for you!"
Maniacal laughter, or growling (mentioned above i think) works really well for startles!!!
As a Cast Manager and a lover of haunts, try to steer away from lenghty dialogue. It slows down the room, and can almost ruin your startle, plus may just be annoying to the customer.
In my opinion, keep it to one to 3 words max. And make it interested to you, so you don't get bored
Do Vegan Zombies eat heads of lettuce?