Other than a hard disc replacement a good few years ago, it's been very reliable...
.. until recently, when it's been acting up a bit.
It's been losing it's network settings, preventing me checking up on things while I'm out via my mobile phone and the "Eagle Eyes" app.
Get home, reset them and it's OK again for a day or so.
Everytime, it resets the network IP address to seemingly random 10.xxx.xxx.xxx address, which isn't compatible with my home network, which is the usual 192.168.xxx.xxx ... It also sets the port number to a random number too ...
Off with the lid ....Not much inside, a small board, the HDD and a small power supply converter...
.... and a very guilty looking CR2032 lithium cell, which proved to be only reading 1.4V instead of 3v ....
Replacing this and resetting the settings on the box has sorted it :)