Manual speed limit assist (Australian version)

[AV8R]

In the owners manual page 5-87 discusses this but when I try it it just turns cruise control off. The manual says press twice I do that and it turns off cruise control. I’m wanting to set an audible alarm when I exceed speed I set. At present there are no audible warnings with regards to speed limits and I would like them. Even the HUD does not flash the speed limit sign in the screen only on the nav media display in the middle of the dash flashes when you go over the limit.
Anybody know how to get an audible warning? I have the GT.