If any of this results in a significantly improved connection speed, then you can rule out a modem or computer configuration problem. Isolate the phone line from house wiring by disconnecting the house wiring from the telco network demarcation block and connecting the modem directly to the network demarcation block. If this works, there is almost certainly a premise wiring fault of some kind and you will have to use trial and error to find the fault. Try another brand and model modem. If this results in a substantially improved connect speed, then the limitation may be modem firmware compatibility or just plain modem quality.
Some modems handle some types of line impairments much better than others.
When talking to the phone repair person, if you feel they are not sympathetic to the issue then ask for their supervisors name and phone number, call and request another repair person. If all these steps do not result in finding a cause which can be corrected, we suggest considering ISDN which WILL provide vastly superior performance and reliability over any analog modem. All Rights Reserved.