I don’t know if there were any DAB trials on in Brisbane back in 2007, but it’s to my understanding that DAB (as opposed to DAB+) was trialled in Sydney for quite a long time:
Upload credit - “MediaWatcherOz”
This YouTube upload is from June 2008 (so probably towards the end, before the DAB+ services we’re all too familiar with now started in August 2009), but the video description suggests that they were running as early as December 2003!