For months, frustrated car owners just couldn’t explain it. Parking anywhere in the vicinity of the Hollywood Police Department would render their vehicle’s keyless entry system useless.Authorities finally solved the mystery, however: beginning in August, a rogue radio station had been operating from the roof of a building just one block away from police headquarters. Aside from broadcasting Caribbean music 24 / 7 to those in range, the station was also blocking the signal between electronic key fobs and their designated vehicles.