It is just the Sensation.
If i take the Memory Card out i cannot use the power button to select any option but can still navigate menu's via the volume button. When the memory card is in, it will automatically select the 'fast boot' section where i am greeted with a message ' Battery Voltage is too low' 'Please Change A Battery'.
What can i do? I don't press anything to go into this mode however it may be possible that something would be jammed.