Channel 4 is still undecided about its future in digital radio, and may even retain the multiplex it won last year to rent space to other broadcasters.
And Channel 4 chief executive Andy Duncan confirmed it is "highly unlikely" that any new C4 national commercial digital station would launch in the next year or two.
Andy's personal view is that DAB could have a successful future – he told MPs on the House of Commons culture, media and sport select committee.
It is thought 4 Digital Groups efforts in the digital radio world so far may have cost them up to £9m.
A Channel 4 spokesman said: "No definitive decisions have been made about the multiplex and we are in dialogue with all our 4 Digital Group partners about the best way forward."