It's usually 1 or 2 of the standard 6 second delay. Note: http://www.sportsyncradio.com/
Someone needs to make a simple device which would be plugged into the RCA jack between a headphone (or other?) device and the RCA jack, which can store and delay transmission to the device for an adjustable time up to a minute or two. A use could be for listening to a sports game on the radio (through local commentators) while watching the delayed broadcast on TV. Call it "Game Day".