Venue 8 Pro Time Massively Inaccurate

I recently bought a venue 8 pro and I'm having problems with the date and time. I'm having to set the time several times a day. If I don't, it will be as much as 12 hours every 48.

Apart from the inconvenience, a lot of apps rely on an accurate clock, for example, the store often refuses to run if the clock has fallen too far behind.

Is there anything that I can try to resolve this?