Can't Stop Disk from Blinking

Hi

I have a FAS8020 running OnTap 9.1

We have a few disk failures and I set the blink on (2.2.5 and 2.2.9).

I can't seem to stop the disk blinking by using either the blinkoff or off command for disk set-led.

I'm pretty sure I have the right disk numbers. Is there any way of listing disks that have blinkon? 

Thanks