unknown error -48 -1303 when trying to sync Ipod Classic 120Gb

Hi,

Since a few days, I'm unable to sync my Ipod Classic 120Gb with Itunes ON windows.

After a few minutes, I get differents errors in Itunes:
+- An unknown Error Occured - 48+
+- An unknown Error Occured - 1303+
+- The disk could not be read from or written to+

or Itunes just keep trying to transfer the same song during hours.

Windows give me such errors:

Windows - Delayed Write Failed : +Windows was unable to save all the data for the file F:. The data has been lost.+

I've already try
-to sync it on differents computers (Vista 64 SP1, XP SP2, XP SP3).
-to restore ipod
-the five R solution
-a chkdsk /F found error but the problem persist after the correction.

Firmware & Itunes are both on last version.

I think the Ipod HD is making more noise, but it might just be my feeling 😉

Has someone any idea to help me ?

Thanks.

P.S.: Sorry for my english, it's not my language.

Christophe.