Once a technician arrives, tell them the troubles that you are having. They will go and check the line for you. If there are any problems, they should fix it. If they don't find any problems, ask them if there is anyway that they can improve the line. Now go for the sensitive spot, ask them how fast they connect at their house.
Most technicians have personal computers and are on the internet.
If they connect fast, they might feel your pain. If they connect slow or don't have internet access, tell them about your weak connections. They might be able to do something or they might not, it depends on your situation. If you use one for voice, and one for your computer, you can have the numbers switched so that you won't have to tell people your new telephone number. See if your Telco will do this without charging you a fee.