Thanks a lot for your reply Len. I don't think I'll ever need the PC/Mac connection then. (Just wanted to understand why it was there so thanks)

I've recently got the M-Audio Duo interface (was bought for Mic preamp) and I have an electric guitar amp so I will try and see if either of these are suitable for picking anything up from the keyboard's line out.

I did however get it working by plugging a lead from the headphones socket of the keyboard to the line in on the Mac! (- the resulting sound quality and volume is fine) I still think it should be done though with the line out ?!?! but hey at least I have some results so far....

Thanks again for your help