Go Essential won't turn on

I've had this before and a factory reset sorted it out. So I did another reset last night. After a few fits and starts it finally reset and updated. I then set it all back up and everything seemed to be fine.
Today I put it in the car and set my route. Everything was fine until I Asked TomTom to turn the volume up. It wouldn't respond.
I stopped the car and tried to enter into the menu. The screen wouldn't respond. I also noticed the screen was very hot (The heater of the car was not anywhere near the device...) I unplugged the power and let it go into standby. I then powered it back up. Still the same. I then just unplugged it and left it on a cool spot in the car for about an hour and fell back onto good old reliable Google maps.
When I tried the TomTom again the screen was still hot but I could enter the menu, but the screen wasn't very responsive. I did a hard shut down then tried to turn it back on. Nothing. Dead as a nit. I've now brought it home and had it on charge for a couple of hours. Still dead. I can't hold the power button on for over 15 seconds to try and force a factory reset either. It's just dead.
Any suggestions?
Comments
I have tried that, but unfortunately it's still dead.
BTW, any idea why it would have over heated in the first instance?
Cheers.
Rick.
To Romania!
Blimey, bet this'll take a while to get back to me.
Anybody had any experience of this type of work and the time taken?
Rick.
Superuser
Has been fairly quick normally I think however Tomtom have indicated they are having issues with getting goods delivered into the UK since you know when.
Doug