How do I get my TV to start up normally wihout being forced to retune?

Philips flat screen TV 26FPL5522 D/05

My TV above will not start up unless I do an automatic retune which takes at least 5 minutes. When I switch on the page demanding the retune is there and I cannot find a way of bypassing it.

If I switch off for a few seconds it will restart normally most times.

I suspect that there is a battery in there somewhere that will not hold its charge for more than a minute or so.

Has anyone else had this problem. The set is hardly used but it is a few years old.

Thanks
Dave