Problem with MyBook World Edition (Blue Rings) - get alternately flashing rings, but drives say fine

WD Legacy Products Other Network Drives
1

So, about once or twice a day, the drive just starts flashing the alternating rings.  I reboot it, get into the web interface and it always says ‘Drive OK’.  it stays up for a few hours and then the flashing again and the inability to get into the web interface until I reboot it.

I feel like a drive is failing, but with no status on the drives other than ‘OK’ I don’t know which one to replace.  How can I figure out what’s going on here?

There are two 750 GB drives in here in RAID 1.

2

Try removing one of the drives an test while connected to another enclosure or computer direct