No/Little water in drum or conditioner tray?

I have a 5 year old (?) Zanussi IZ16 washing machine that has been working fine for most of its life. I noticed a while ago that the conditioner was not being taken from the drawer and so i cleaned the drawer and checked the siphon action (all ok), but this did not resolve the problem. I then tried watering down the conditioner, but this still did not resolve the problem. Then, recently i've noticed that the drum doesn't fill properly with water during a normal cycle. I've tested the water pressure comming into the machine (3.5 bar) and I think it is adequate. I also checked the inlet filter and this was clear.
Any ideas on what is stopping the water from entering the machine?