Anybody had trouble doorbell ringing and nobody there?

I have one of those for the front door. Difficult to wire up electric one for back door.

We had this problem in our previous house. We eventually realised that our neighbours remote car key worked on the same frequency!!

We had same problem and when we changed frequency in bell it stopped. Also neighbours car key also set something off.

We had this at 7.30 am last Friday. The doorbell rang and when I got up and looked out there were no footsteps in the snow outside so it seemed very weird at the time. Turns out we had a very brief power cut which made it ring when the electricity came on again.

HurdyGurdy

Yes, had that - but not for a while, come to think of it. Assumed it was, as has been said above, someone else with a bell on the same channel.

But randomly, the tv in the bedroom will switch on at precisely 3am. Never a minute either side!

I've taken to pulling the plug out at night

Regarding your TV set switching on automatically -

I was having a similar problem and found that 'somehow' I'd manage to set some kind of TV Programme Auto Switchon. I found it when I went into 'Scheduled Programmes' - apparently I'd done some kind of 'Series Link' which meant that EVERY TIME this particular programme came on, my TV automatically switched over to it ........................ even when the TV was switched off. It drove me mad till I managed to 'unprogramme' the schedule.

On one occasion, my husband was asleep in front of the tv but woke up with a start owing to a doorbell ringing on the programme. He gave me such a filthy look, I knew he was thinking 'aren't you going to answer the door, I've just woken up' so I said 'it's the telly'.
He stomped out to the hall, only to return saying 'there's no one there'. I laughed my head off.

this used to happen to me where I lived before. It turned out to be someone parking nearby and using a key fob to lock/unlock their car. Quite unnerving if you live alone!