washing machine?

When i set my washer off on a cycle, the drum fills up with alot of water nearly full,(which shouldn't happen with this model) the clothes get washed ok, then the rinse cycle works as it should. however this doesn't happen all the time(1 in 5 washes is ok) but now it's doing it more frequently. I've done all the ususal checks Can you help?

Model: Marherita A1535 Advantage