Sonnet Raid D800 - have I set this right?

Hi guys - Jeremy in particular if you would be kind enough to read this please as I think you also own a Sonnet D800?

I'm a little concerned I maybe somehow haven't set up my Sonnet D800 properly as I'm experiencing a slight 'hang' in FCP6.

In the instruction booklet it states: "some applications may benefit from modification of the controller's NVRAM settings that tune the controller for a specific performance range."

When I wrote to Sonnet requesting configuration details for my particular setup to get best performance they replied:

"Peter, Sonnet normally ships the D800 (when configured with drives) as a RAID 5. We use the default settings as outlined in the instructions in the attached PDF. We do not have any special settings for using the D800 in a particular environment or purpose. Once you have your drives installed, please see the attached instructions on how to build a RAID 5 on the D800."

I'm getting the little 'timer' circle popping up 'hanging' during scrubbing (fastforwarding or fastrewinding) of material in the viewer of FCP6.

I've made my playback 'low' quality and unticked 'scrub high quality', turned filevault off, trashed prefs, but am still getting the hanging every 10 mins approx (each 'hang lasts about 5 secs' but can be pretty irritating).

Just as the hang occurs I can hear my Raid whirring louder than usual, as if getting a key turned in its ignition.

I have included my RAID properties below - is there a way I can scan/test the Raid to ensure I'm getting maximum speed out of it? I see lots of little 'fine tuning' options but am scared to touch them in case they screw up all my hours of captured video!

Raid Type: RAID5
Capacity 5.46TB
Members: 7
Partitions: 1
Mirrors: None
Interleave: 128KB
Sector Size:512 bytes

Drives: 8
Faulted: 0
Raid Groups: 1
Hot Spares: 1

Features:
Speed Read - Always
Rebuild Priority - Same

Prefetch: 0
Auto Rebuild: Yes

In my ATTO Configuration Tool for the Sonnet D800 it states under NVRAM:

Heartbeat: Enabled
NCQ: Enabled
Device Wait Time: 3
Device Wait Count: 1
Spinup Delay: 0


I'm using a:

2 x 2.66 GHz Quad-Core Intel Xeon
8 GB 1066 MHz DDR3 ATI Radeon HD 4870
Mac OXX (10.5.7)

Any thoughts would be really appreciated.

All the best

Peter