Postado originalmente por 
wirelessmain
				
			 
			Conforme havia comentado, veja se te ajuda em algo:
 
No Mangle:
;;; Generic SIP port
chain=prerouting action=mark-packet new-packet-mark=voip passthrough=yes protocol=udp in-interface=Speedy dst-port=5060 
 
 
chain=prerouting action=mark-packet new-packet-mark=voip passthrough=yes protocol=udp in-interface=Speedy dst-port=16384-16482 
 
chain=prerouting action=mark-packet new-packet-mark=voip-sip passthrough=yes dscp=26 
 
chain=prerouting action=mark-packet new-packet-mark=voip-rtp passthrough=yes dscp=46 
 
Queue tree
 
 
name="VOIP" parent=global-total limit-at=128k priority=8 max-limit=128k 
burst-limit=0 burst-threshold=0 burst-time=0s