Incoming calls ring once

is it possible for incoming calls to ring once and then sit quietly or at least make it ring less frequently? This is from a queue btw. I have this at my shop and Id like to be able to finish up a conversation with a customer before I answer the phone.

I guess you could put a time on the dial, i.e
exten => 123,1,Dial(SIP/100,5)
exten => 123,2,Wait(whatevertime)
exten => 123,3,Dial(SIP/100)

just throwing it out there, havent tested it