Right guys, first post, and tried a quick search but not found anything specific enough to solve my problem.

My iPhone was set up originally to the Macbook...apple to apple is always better IMO. Since then I wanted to update music that I have stored on my PC...and this is where apple are wrong and stop more than one machine syncing without wiping what was originally placed on the phone from the missus's collection. Non of the music is DRM as i rip them myself...huge record/cd collection as I dj.

I back up all my stuff using the PC though, and the external hardrives are in windows format and cannot be truly read by the Mac so no chance of just plugging it in to the Mac and updating using that.

Anyways around this?

I have even placed the playlists into iTunes on the PC and tried to drag and drop like I do with the iPod but this doesnt even work...just the O with a / through it

This is ridiculous that all this is legit and yet apple wont allow an obvious work around