exten => 8000,1,NoOP(Starting my loop);
exten => 8000,n,Answer(); Answer
exten => 8000,n,Wait(1); Wait one second before playing voice file
exten => 8000,n,Background(vm-goodbye); play voice file
exten => 8000,n,WaitExten(2) ; wait for user input

exten => t,1,NoOP(Time out extension i=${i})
exten => t,n,Set(i=${IF($[1${i} = 1]?0:$[1${i} + 1])}) 
exten => t,n,GotoIF($[${i} >= 11]?t,100:)
exten => t,n,Goto(8000,1)
exten => t,100,Hangup