I have had no problems with the -323, but this just happened today.  The drives were removed to transfer a lot of data onto them, something that has been successfully done before.  When they were put back into the -323 & the power was applied the power light flashed blue once & then the left drive light illuminated amber.  The right drive light did not illuminate.  The unit will not boot any further & cannot be located on the network.  I attempted to access the drive through my web browser & had no luck.  The only way I could power down was to pull the power plug at the back.  I put a fresh (not formatted) drive into the right slot & powered up again.  Same result.  I tried a factory reset for 20 seconds with the power on & no change.
The firmware is 1.07 & I cannot go back to an old one as I can't access the unit. 
Any ideas?  Has the unit failed?  It will be a bit hard to replace it, as I purchased it in Australia & I am living in Dubai.