[Hilton]

Update: I have managed to get the audio by using Internet Download Manager! It downloaded as an FLV and I then used FLVextract to demux it and just get the audio. Perfect, thanks again for your help Josan.

I am still interested to know how rtmpdump works, and if it is a better alternative to Internet Download Manager. However...using IDM was very very easy so it's a no brainer in terms of time efficiency.