i have a medical customer and they have the summit aa set to pick up all calls and play a message- if an emergency hang up dial 911, and for an operator dial 0. when they dial 0 it rings 4 phones in a ring group. i called them today and the first time after dialing 0 there was a pause and then i heard a dial tone. the second time it went to the ring group. does anyone have an idea why it doesnt always work. thanks dave