We have implemented a VoIP solution for a customer using a Draytek IPPBX2820N router connected via WAN2 to an 8MB/768K (5:1 contention).
There are 10 Grandstream GXP2000 VoIP phones attached to this system, and I have configured outbound QoS for their IP address range and given them 40% of bandwidth, as per the example in the webinar tutorial.

Does anyone know of any different or additional settings that should be used in order to optimise call quality in this scenario ?