'Hard Resetting' of its own accord

[mark-1]

In the last few days my XDA has been Hard Resetting while working in an application. Then when reconfiguring and performing a soft reset it actually performs a Hard Reset. Also occasionally after eventually managing to restore the config, the screen has shifted upwards by 7 pixels so the top of the telephone icon cannot be seen.
Has anyone experienced a similar problem; internal component failure, dodgy internal battery.
This product is under warranty and will probably have to return to the service centre unless a solution can be found

sw config: ROM 3.02.00 ENG, Radio 4.01,Protocol 324e2

Thanks,

mark-1