Slow internet speeds equate to breach of contract

I am paying for a 4 Mb home broadband connection, but the line consistently syncs at 1-2 Mb, less than HALF of what I'm paying for. The Neotel contact centre has not been helpful at all. I have repeatedly tested this with all downloads stopped and all devices disconnected from the network, and the router still registers a maximum speed of 2 Mb. <br> <br> This needs to be fixed as soon as possible, or else it equates to a breach of contract.