600 GB My Book performance is lagging, no errors detected on drive

I have a 600 GB My Book external drive that is a few years old. It has worked beautifully up until the last couple of months. Access times are becoming gradually slower on devices like my DVD player, my wd live tv device and my various PCs. It can take upwards of a minute for my DVD player to access the drive, whereas before it would take 5 seconds at the most. Same with the wd tv device. Indexing the drive takes forever… I’ve run error checks that say that the drive is fine, and Windows 7 reports that it has 0% fragmentation on the drive, so I don’t really understand why the drive is having progressively slower performance and access times. Is it just a matter of wearing down from usage over time? I don’t really want to format the drive and start fresh if I can avoid it. Are there any things I can do to speed up the drive?

It’s formatted with the fat32 filesystem.

Try formatting on NTFS for better performance

besides that, not really much that can be don AFAIK