Superfibre broadband but only 30mb?

i've been with talktalk for a few months now and not once has a speed test gone above 35mb. I'm on the 76mb broadband and i'm connected at 79999 in my router. It's impossible to watch netflix on 2 different devices without noticing considerable quality loss. Gaming is a no go when someone is watching netflix aswel. This is completely unacceptable, I mayaswel be paying for the 40mb package.

If it's a DLM profile issue then can you switch mine to speed please?