Almost no speed with my own modem, unable to use internet - 1 mbps upload & 1mbps download?!?!

My internet connection is cycling between acceptable speeds and virtual zero speed at all. from 96 mbps download & 41 mbps upload all the way down to 1 mbps upload & 1mbps download. When it's that low web pages won't log, I can't upload or download I can't stream, video quality is degraded. I don't need super fast speeds - I don';t do gaming and I don't download huge files - mostly MP3s and compressed music files but I can't even do that at times. Why is it so slow? I have had techs come to my house and they cannot fix, they say it's all ok when it's clearly not. No one on phone has helped, every time I talk to a new rep I get the run around, the contradict what the last person told me. Every time it's a new story. Please help!!!!!