I had the same problem with intemittant ethernet connections during upload / sync in Emplode and Ws_FTP. I ended up re-installing Hijack and my problems went away. I'm not completely sure why Hijack would have anything to do with this, but it worked for me. I normally sync my players with Ws_FTP and I tried the Hijack route because I thought it was something to do with my FTP connection to the player.