Pure Tempus-1 forgets its programmed radio stations?

Does anyone know what the fault could be when my dab fails to remember any radio stations. It rescans on every power on. Could it be as simple as a dead battery cell for memory back-up? I haven't opened it up yet. There is also very poor LCD backlighting. It functions but is dim.
I think pure hire a bunch of numskull design engineers. There is so many common faults with this radio and my bathroom pure radio battery charging system is a joke.