Petroleum jelly wouldn't work around here; too many of my monsters like to eat it right out of the jar. I've used dish soap, straight, slathered onto the wires, and the clear beverage tubing from the hardware store. Tubing saved the last 2 TVs; it seems to ruin the mouthfeel of the wires. We mostly had to wait for them to (mostly) outgrow the habit. The cursed curly phone cord, however, is irresistible to this day, as are flip flops and plastic clogs.