A/v receiver - sony STR-DG700. No surround sound from tv [optical output] when broadcast is in dolby .?

Question

everything else works ok [see below]. even reset the unit to default factory settings etc, but can't get dolby digital surround sound to come through the 5.1 speakers on HD broadcasts or anything. when we first set it up we could, but something changed [somehow] - now not getting any sound at all through receiver [on video1 which the tv's optical is in]. have checked the cable is plugged in of course - can anyone suggest what's wrong here ?

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Answer 1

the optical cable may be broken can you see a light on the other side, if not try another option maybe coaxial