HOOVER SIX 1300 WDM30....OVERFILLING WITH WATER?

HELP...my washing machine has been overfilling with cold water at the beginning of wash cycle,its flooded my flat twice,it dosent do it all the time,also ocassionally theres a loud sharp squeal from the drum...these problems arent present all the time....i would be gratefull of some advice.....machine is 3 years old...its covered by a basisic parts guarantee with hoover but there is a charge of 85 quid,which is for labour and call out fee...do you think this is reasonable..im hoping to be able to fix problems if they are mot to serious,,,please advise...best regards....graham