N4100 loses all data after power outage!

I couldn't find anything in the search about this, so here goes.

We have a N4100 1TB RAID system. It's been working fine for over a year as we do backups to it from our servers. Yesterday, it accidentally got powered off without being shut down properly first.
When we switched it back on, all the drive lights were flashing, and it said something about rebuilding the RAID.

All our backups had gone. Over 500GB of data, wiped out in a flash.

I'm not impressed. If it's going to lose all our backups if we have a power cut, then it's as much use as a chocolate fireguard.

Has anyone had a similar problem? I've upgraded the firmware in case this was a problem in an earlier firmware version and now fixed, but really I feel we can never trust this device again.

Dear Sir,

Please mail to support@thecus.com and let we know this N4100 power break on what version firmware, also if possible please provide an IP address & port 21/22/80/443 for us to analysis & found the possible issue out, following three ways to publish the NAS on the internet for your reference:

1.
Public Fixed IP (most easy)
Just assign a public fixed IP on the NAS WAN/LAN1 port

2.
DMZ (easy)
Enable Router DMZ function and fill in NAS WAN/LAN1 private IP in the Router DMZ column, and then tell me the Router WAN IP.

For Example:
Router WAN IP is 139.175.55.244
NAS WAN/LAN1 IP is 192.168.1.100

Enable Router DMZ function and fill in 192.168.1.100 for DMZ, thus the Router will forward all connection of 139.175.55.244 from internet to NAS WAN/LAN1 IP 192.168.1.100, than I could access to the NAS.

3.
Virtual Server (port forward) (a little difficult)
Assign port 21/22/80 and 443 forward to NAS private IP, following case study about port 443 for your reference: http://www.thecus.com/storage_case03.php.


Yvon.