Writing for future reference.
I purchased Onkyo Tx Nr717 from amazon.de 2012, I live in Oz.
I started to have issues with audio. Onkyo 717 HMDI no sound (actually an issue with all inputs including analogue, TOS etc)
Selecting different inputs and changing surround mode then powering off and on 3 or 4 times can get it running again until you power it off. Start the procedure again etc.
Onkyo dealers will not even look at my receiver due to it being an import.
I have heard the board cost $450 which I was willing to pay but no one would sell it to me so I looked into it further.
I found a link on youtube How To Fix the Onkyo TX SR606 HDMI Input Problem
You will have to search, this site wants 5 posts before I can add a link.
I ordered a dozen of these and replaced them. All is good.
You know were you can stick it ONKYO. Cost me $6.00 !