I have a Cambridge Audio receiver, Azur 540R. After 2 months, now I have a problem! It works fine with "DVD" and "6.1 direct" input, but no sound from all the other inputs. No tuner, no video1, video 2, video 3. Nothing. At the beginning it was all right, but 2 weeks ago these kinds of problem appeared. Sometimes it happens that you hear the same source, indipendently of the selected input. For instance you can get the radio from any selection, or the video1 sound, but most of time you get nothing at all, with the exception of "DVD" and "6.1 direct". What could be the reason of this mulfunction? Never happened anything similar with other equipment. Can someone suggest something? Thank you and goobye.