How can i fix my Pure DAB Classic radio?

I have the above radio that will only work for 15 minutes at a time.It the cuts out.The time and station on preset will not change amd the volume control will also not change.
I went onto the Pure website last year and didnt follow the enquiry all the way through as it was quite a lengthy process
They did tell me that I needed to download some softwear into the radio that would rectify the fault.
Can you advise?