Jas, sorry for replying to your message so late. I may have figured out a solution but it depends on you. Like Micro mentions, it may be something interfering with your cable transmission. Now, I want to add to that. It may be the music player that you're using to sync your files. When I was still using Windows my music player of choice was Media Monkey Gold. It's a great music player but it was the root of my syncing problems. When I switched over to ubuntu, which is another flavor of linux, all of my problems have gone. In fact, I removed all of my music and created a new sync. Not only did all of my music sync quickly it was really fast. Ironically, if I were to sync my Mum's Sony MP3 Player with MM her player syncs fine but it's not lightning fast.
My recommendation is to identify any programs that may be interfering with your transfer and let us know what audio program you're using to play and transfer your music with. That may be the problem. Just my thoughts though.