If You Muzzle a Dog, Will That Stop Him From Barking All Night Long?

No, for the past year, I’ve put up with constant barking. We’ve taken him to the vet, he has no medical problems. We’ve tried sleeping with him, sitting with him, excercising him in the day so he’s tired at night, Eeping a light on, making no noise, keeping no lights on, keeping a nightlight on, keeping all the lights on, we’ve tried feeding him less, and feeding him more. We’ve tried letting him, we’ve tried closing the blinds, we’ve tried blocking the back windows, and we’ve tried comforting him. We’ve tried hunting outsidefor things bothering, and hunting inside. We’ve moved our cats out, and we’ve let them stay with him. We’ve tried pretty much everything, and invested a lot of money. Any ideas?