Question about using FTP for synching

Been using WS_FTP to sync my players for a few weeks now. Had initial problems because I didn't read the FAQ and hadn't set my transfer setting to Binary. Got that sorted out and re-transferred the info from Drive0 and Drive1 on my master player to my PC. After that, instead of using the Synchronize tool in WS_FTP, I just did a transfer using the arrows (you know what I mean I hope) to one of my slave players to make an exact copy of the drives. Now when I use the Synchronize tool in WS_FTP to actually make a sync, Drive0 works fine, but Drive1 wants to sychronize the entire dirve (all files, approximately 20gb of info). What could be the problem here?

My guess would be that the time stamps on drive1 are for when you copied them, and not the same as the dates on the original files, the setting of which, if this is the case, is one of the things that your synchronize tool does that simply copying does not.