Have you had a look at the smartctl -a outputs of all the drives?
Possibly one drive is being slow to respond due to seek errors etc. but I would perhaps expect to be seeing this in the log.
If you have a full backup and a spare drive, I would probably rotate it through the array.
Regards, Richard - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
