It's actually a phone number that Suncorp/GIO Insurance phone on. When you phone the number back there is actually a message service saying this. It also says if it is necessary they will phone you back, and there is no need for you to take any action.
So despite seeming like a nuiscense call it is actually a great service!
I had 4 calls in 4 days, but it was fairly urgent. It was suncorp asking if I wanted to continue insurance with them. I had accidentally let it lapse for my scooter for two weeks and somehow didn't receive a renewal notice last month.