Pathetic Service From Home-Connect

We had a 25mbs line installed, we used normal internet on phones, etc. which was fine, I then subscribed for Internet TV and I was told that a 25mbs line is more than sufficient but we experienced bad buffering from day 1. I was then advised to upgrade to a 50mbs line and we were still experiencing the same. I have colleagues that are using the same Internet TV provider and when mine buffers theirs is stable. How do you explain this. HomeConnect then blames the Internet TV service provider. Now Home-connect's excuse is they only provide internet, they cannot resolve issues faced in my home. The line was also tested once by Metrofibre but I did not receive any formal correspondance confirming that this is in order. I submitted more than 8 Logs and the responses has been extremely slow. They also never call you back when arranged to do so. Stay away from companies like these because they are very quick to debit your account but do not provide the required afterservice