Listening to the initial boot up, it sounds as though the hard drive is broken. It makes almost a beeping noise.
When i go into the maintenance menu, I have tried all of the options (factory reset with and without keep recordings), the only one which works is software reset, but that enters the device back into the start up cycles.
I have tried booting up with and without the device connected to the network, and it still doesn't work.
It's over 2 years old, purchased August 2014 so out of warranty.
Is there any hope, in your opinion, BT will replace the box for me?
I have also seen that people have replaced the hard drive and that works - do you think that is an option?
BT will replace it wth the newer box, but if you are out of contract, they will insist that you renew your contract.
The newer box is much better, and a lot smaller.
Try vision live chat
You could try changing the hard disk, but they need to be a special type suitable for recording video.
If you are happy with the service, I would just renew your contract and get the new box for free.
BT UK customer options on 0800 800 030 is a good place to start, and you are likely to get a good deal, which may be less than what you are paying already.
Interesting as I was about to post a virtually identical message. The other coincidence is that our box is roughly the same vintage. worked fine until last Sunday .
It makes a buzzing noise in a pattern that then repeats every few seconds.
Like the OP I have tried every option on the maintenance menu and after each I get the message that reset has failed.
I have the details of a suitable candidate HDD but don't want to splash out if that is not the problem.