Hello again,
Sorry to be a pain but the problem is back.
I appears that putting it in sleep or hibernate manually is ok. But closing the screen and putting it into sleep that way means that it does not turn on properly. I had to take the battery out this morning and use the mains to turn it on then put the battery back in. Although I had powered it down it turned on as if it had been in hibernate once I did this. I can't think of anything else I can do to solve this.
Hopefully you can help some.