You can register with external advertising agencies and place your own advertising on your pages.
XtGem is in no way responsible for the content fill rate or quality of external advertising
Nor is Xtgem in any way responsible for any non payment or suspension of your account with external advertising agencies
First off, register an account on the chosen advertiser's site.
Then include one of these codes,
changing site_id (and zone, in case of mojiva, publisher_id and adspace_id in case of smaato)
Along with your advertising company account id
You can find these parameters either somewhere on their site while logged in
Or extract them from one of their provided integration codes (PHP/ASP/etc)
If admob doesn't return an ad, nothing will be displayed in the first code instance and buzzcity code will be executed
If admob does return an ad, buzzcity will not be executed
Second admob instance will not be executed either way, as it's a duplicate call
To insert a second ad on a page insert adid="2" into the second ad code
It is also very important to note that you might not see ads on your site at all !
This is NOT XtGem's bug !
Either your site has not been accepted by the ad network
(you can usually check your site's status on ad network's site)
Or they do not have any ad inventory with targeting matching your country/browser
Despite that, your site visitors might still be seeing ads
Check your ad network's stats to see if ads are being delivered