iOS 5b5 syncing issue - not enough space

[The DRis]

When I try and sync my iPhone 4 running iOS 5b5 to iTunes 10.5b5 it gives me the error "not enough space to sync iphone, addition 6.3GB needed".

Anyone know why?

 

[The DRis]

Nevermind. For some reason it wanted to sync my music onto the iPhone even though the music was already there. I unchecked music, synced the phone, rechecked music and synced again. All fixed.