Unacceptable internet service.

We have been residing in this residence since September 2010. Since then we have had very bad internet reception with it dropping the line constantly and once you have access it is extremely slow. This problem has been reported on numerous occasions and has had numerous technicians attending with no resolution to the problem! Every time the problem is reported it takes several weeks for the technician to attend to the problem in any case. Once they get here everybody has a different story i.e telephone line filters, broken telephones, etc. They fiddle around with these but the problem remains. Nobody either with the call-in centre, nor the technician will come forward with a straight answer or solution? Other people in the suburb don't seem to complain about the same? In the meantime we pay diligently every month for line rental and internet, but no service. I need an honest straight answer saying that I should rather end the service because it can't be fixed and be refunded for services not received or fix the problem. Regards.