Mac wireless diagnostics on Dome: How to change Wifi Country code from US to AU


Hi Have run Mac wireless diagnostics on my Dome and it is configured to US while we are in Australia and fear it may be the cause of some of our wireless performance issues eg internet access dropping out every 15 minutes or causing the Dome to have half the speed of the modem/router.
How can I get this addressed? also noting that I do not have the option to select wireless channel either.

Country Code - China?
Koalasafe (Dome) offline