Alaska’s DUI law specifically mentions a motorized vehicle. So you probably couldn’t get a DUI on a horse, in a carriage, or with a dog sled, but if they were pulling your car with dogs then you might. The law doesn’t specify the motor be on, or functional, just that it be a “motor vehicle”.
I guess it would come down to the jury on that one.
I don’t know if it’s still a thing in the digital age, but having even just a few seconds of dead air back in the analogue broadcast days could mean that “silence detectors” all over the country would start going off and radio engineers everywhere would think there was some kind of problem with their station. So there had to be talking, music, something at pretty much all times.
If you wanted intentional silence you could play comfort noise in the background.