Google search cache points to and uses content from different url

[ArchMedia]

We have two sites, 1 in new zealand:

ecostore.co.nz

and 1 in Australia:

ecostoreaustralia.com.au

• Both sites have been assigned with the correct country in Webmaster tools
• Both site use the same urls structure and content for product and category pages
• Both sites run off the same server in the US but have unique ip adresses.

When I go to google.com.au and search for:

site:ecostoreaustralia.com.au

I get results which google says are from the Australian domain yet on closer inspection it is actually drawing content from the NZ website.

When I view a cached page the URL bar displays the AU domain name but on the page (in the top grey box) it says:

_This is Google's cache of http://www.ecostore.co.nz/pages/our-highlights. _

Here is the link to this page:

_http://webcache.googleusercontent.com/search?q=cache:Zg_CYkqyjP4J:www.ecostoreaustralia.com.au/pages/our-highlights+&cd=7&hl=en&ct=clnk&gl=au_

In the last four weeks the ranking of the AU website has dropped significantly and the NZ site now ranks first in Google AU, where before the AU site was listed first.

Any idea what is going wrong here?

[AgentsofValue]

Hi - I can't say I know 'exactly' what's happening here, but there's something strange about how your A records are setup for your DNS.  For the sites I host, I have a single A record for the www. and another for the non-www for the domain, and they both are assigned to the same ip address.  When I view the A records for your sites, they have a variety of different A records set.

;; QUESTION SECTION:
;www.ecostore.co.nz.            IN      A

;; ANSWER SECTION:
www.ecostore.co.nz.     600     IN      A       174.129.212.2
www.ecostore.co.nz.     600     IN      A       75.101.145.87
www.ecostore.co.nz.     600     IN      A       75.101.163.44

;; QUESTION SECTION:
;www.ecostoreaustralia.com.au.  IN      A

;; ANSWER SECTION:
www.ecostoreaustralia.com.au. 3388 IN   A       75.101.145.87
www.ecostoreaustralia.com.au. 3388 IN   A       75.101.163.44

The non-www's seem kind of random as well.  I'd talk with your hosting provider and see if they can help you clear this up.