There are a lot of myths that say you can get rid of squirrels with bright lights, loud music, or apple cider vinegar. None of these methods work. The only way to get squirrels out of your attic is to call a professional to trap them.
Squirrels have a pretty high tolerance for almost anything if they have found a safe spot to bear and raise young. Your attic is it…no matter how bright or noisy it may be.