Two members of the Labor Party's shadow cabinet have called on Prime Minister Malcolm Turnbull to provide details about how the anticipated lack of income from the national broadband network will affect the federal budget.

What's wrong with Australia's national broadband network? That's a hoary old chestnut which has been asked and answered many times over the last five years or more, so when the ABC ran a programme asking the same question, it could only come up with the same answers as before. But in much less detail.

In damage control mode again, this time ahead of an ABC programme apparently detailing more of the same issues with the NBN that have been widely publicised, NBN Co chief Bill Morrow has said that the network will never make a profit unless it is protected from competition.