Iphone 4 wont sync Music

Hi have been struggling with my iphone 4 for nearly a week now. tried to restore it and got the dreaded error 14 so took it back to an apple shop and they replaced the phone. They also installed the latest OS on it and told me to install it as a new iphone in my itunes which I did. The trouble is I keep getting these messages while trying to sync my music from Itunes-
'Attempting to copy to the disk"libbos iphone" failed.An error occurred while reading from the device.
followed by
"The iphone "libbos iphone" cannot be synced. An error occurred while writing to the device"
ALso
Itunes could not copy(song title) to the iphone "libbos iphone" because the file is corrupt and could not be read.

"The iphone "libbos iphone" cannot be synced. The required disk cannot be found"

But it seems to sync my apps??

I have tried deleting all my songs from itunes and adding a couple of albums back and trying to sync them but keep getting the same error messages as above.Also I have uninstalled itunes and all other apple programs and re-installed them again.
I am using a sony vaio laptop running Windows 7 64 bit.
Any help would be of great assistance guys!!