Radio Maintenance, not enough dispatchers, God...who knows....more then likely, in the past they have doubled up dispatches becasue they have pulled dispatchers for special operations on differnt channels and left one or 2 to fend for them selves with the rest of the city. With the system having encrypted talk groups now, that is probably a likely occurance to happen more often. During the riots in 2002 (was it that long ago?) they restricted Channel 1 (District 1) to just riot traffic and moved all routine disptaches to Channel 3 (District 3) Tenmporarily and then over to Channel 8 (inquiry) for the remainder of the time. Most likly scenarios are Radio Maintence, Special ops or just short of Dispatchers.