cold water inlet valve letting past. (possible new valve replacement)
hold water inlet valve letting past (ignore if cold fill only)
check drain hose could be filling from the connection to sink if fitted this way (back siphoning)
cure
turn the washer isolation taps OFF after each wash . why do you think they were fitted
raise the height of the drain hose to just under the top of the work unit unit (water don't like running up hill )
wirecutterman
May 2010