Hi
not being rude but have you tried to plug in a differnt phone to your line as the phone might have a fault,
and even more so not wishing to offend but do you wear a hearing aid if so there is a T position for use with phones other than that you need to try perhaps a neigbours phone plugged into your house and see if that fixes the problem if so then buy a new phone
Good luck
Marconi
September 2010