Issue with Adaptec Storage Manager

The issue we are currently experiencing with the Adaptec Storage Manager is it will show the physical drives as optimal but the logical drives (using RAID 5 configuration) show as degraded.

Currently server layout:

Chenbro Chassis (41416)
Intel D865PERL mobo with Intel P4 3 GHz Processor.
2 Gigs of RAM
16 x 500 GB Hitachi Deskstar SATA Drive
Adaptec 21610SA RAID Controller
Windows XP Pro sp2.

Does anyone have a suggestion for correcting this issue?

Dan