How can I fix my Zanussi ZWF1437W washing machine?

Can you help please? Our Zanussi seems to have an intermittent fault. Basically, you choose your programme, it thinks about it for 10 seconds, then jumps to drain, thinks for 10 seconds and switches off. Sometimes it chooses to run the programme and other days only the above. It was making the right noises up until yesterday and now does the same procedure but hums instead. The rinse and spin cycles still work when manually selected, the wash doesn't.

Fed up with playing mind games with a machine! Any ideas please?

Dawn