Really poor service

We are experiencing problems with line speed, over and over and over. Every time I report this, I get called by a Techie who tells me he is doing adjustments to my router online. Then it works for a day or two and then back to poor line speed again. And the excuses are getting more creative by the day. I have asked many times, "tell me what to do to get better linespeed" yet adjusting the flippen router is the only answer they have.