Hi, i have setup my Intercom doorbell with FreePBX sip
all is working, all android devices are ringing when someones presses the doorbell
but, because of they are all ringing untill someone picks up, thats a little bit noisy 
is it possible to make it ring for like 45 seconds, but only with a short notification sound NOT in a loop ?
i have tried several clients like Zoiper, linphone, android natie SIP
but i never can pick somekind of notification sound for an incoming call, i always need to choose a ringtone
thnx in advance