I just received my 5th call or so but this time it was from (03) 9831 4900 which, from what I can tell, is yet another Telstra number.

Yeah, I had the same thing happen to me.

I received a call from (03) 8808 1000, and no one answered only music was playing.

This is Telstra.

And I just received a call from (03) 9246 4700 and then hang up when you answer. Pretty sure it's just another Telstra number. Getting pretty sick of this!

Pretty sure the (03) 8808 1000 number is Telstra. I've received a few calls from that number this morning, though I haven't answered, and I'm constantly being called from (03) 9834 2300 also, which I know definitely IS Telstra. So I just don't answer. My friend was constantly getting calls from another number similar and he answered and they wanted all his details so that they could get in and look at what plan he is currently on to try and offer another, or something along those lines. Not convinced it was Telstra, since they should know his details and not have to ask. Either way, he didn't give them anything. He was receiving these calls at least twice every day until he finally answered, had a go at the caller and requested he be taken off their list.  As far as I know he hasn?t received anymore calls.