When I've dog-sat and cat-sat, I didn't like leaving them with the house and neighborhood quiet. I would leave on the TV or one of the YouTube channels for pets.
This is a hack that many homes should use for two reasons. The first is for safety reasons as leaving the TV on would make any intruder believe that someone is actually home. The second one is that having the dog or cat watch the TV gives them an escape from boredom with something they can look at when you are away from home.