Edge Router Lite 1.9 Simple QoS for VOIP Server

We have an ERL with newest 1.9 fw.

Our network has a TWC 25/2 internet but we're getting a new Fiber connection Gigabit down/Gigabit up.

We have a VOIP Server on site for our phone system (Asterisk based system).

I would like to set it that any traffic coming in or out of the server, IP ADDRESS 192.168.0.4, gets as much bandwidth as it needs.

Any advice on this?

Thanks