Cannot turn off TS-870 Pro

[Cooty]

Hi,

I can't turn off this device easily. I have tried using the following methods:
- Web interface -> shutdown = the NAS reboots
- IOS App -> shutdown = the NAS reboots
- SSH -> "sudo shutdown now" = the NAS reboots

Googling suggests that this isn't a common problem - ideas?

Additional info:
I am running the latest f/w - but have always done this and the problem has been around for at least the past 4 years.
I also run a TS-453BE (and had a TS-410 previously) and these both managed to shutdown rather than reboot when requested.

Hopefully someone here has some ideas?

Thanks in advance,

Cooty