TV/VCR/Stereo Troubleshooting/Denon AVR-988


AVR-988 Display
AVR-988 Display  
QUESTION: Hello.  I have an issue at work.  When playing a DVD (Dolby Digital/surround), audio is no longer passed from the AVR to the console when a digital input is used.

Setup: Pioneer DVD-V5000 connected to Denon AVR-988 via digital coax cable

Pre-outs are connected to Yamaha LS9/32 mixing console via MYGDAI slot card.  

These are the only physical connections used at present.  Video portion takes a different route altogether

On AVR display, both input and output lights indicate proper signal is being input and output, but nothing gets to the console.

However, if I connect the stereo RCAs to, say, the DVR input on the AVR-988 and switch the input to DVR Stereo, the stereo signal is passed to the console.

After extensive troubleshooting I am at a loss, and wonder if it is something simple-stupid that I am missing here.  Maybe someone "hit a button" at some point.  Since it worked properly (as advertised) for and extended period, and now it suddenly does not, that is my gut feeling. But I don't know.  I have already spoken with Denon tech support, and they were unable to help.  I have tried several different devices with digital coax output to no avail.

So in summary, the unit works and sends signal out the pre-outs when an analog signal is input.  But when a digital input is used, selected and detected, no signal is sent (even though the display indicates that it is being output).

I guess it may be time to simply reset the AVR microprocessor??

Thank you in advance for any info.

ANSWER: My immediate thought is you are connected to the wrong connections on the back panel!  Check the ins/outs and see if that doesn't aright the system.

Let me know.

---------- FOLLOW-UP ----------

AVR Digital
AVR Digital  

AVR Analog
AVR Analog  
QUESTION: I have checked that, and unless I am insane or missing something silly, it looks right.  I have attached images showing:

1) Digital input connection on back of AVR
2) AVR display showing that input signal is present and (apparently) output
3) No signal at console

4) Analog connection added (used DVR analog input on the AVR)
5) AVR display after having manually switching input to DVR stereo
6) Signal at console

Incidentally, I did reset the processor (has not helped)

In the above two scenarios it looks like

AVR "sees" the input signal and believes it is outputting (which, if my understanding is correct, shouldn't even matter when using the pre-outs, right?).  But in reality nothing is coming out of the pre-outs.

AVR "sees" the input signal, outputs a signal, and a signal actually does come out of the correct pre-outs.

what am I missing?  Thank you

What about tape monitor switch setting?  (If it even has such)....

Next thought -  the Dolby settings. Digital Dolby maybe has some preset conditions.  Even though I used to work for Denon I don't know the ins and outs of the newer receivers.  I do know that not all Dolby settings have the same functionality.  Suggest you monkey around with that angle.

From my personal experience I find that the obvious is sometimes the last to be checked.  Today, for example I started losing my Internet connection.  The demodulator and router seemed to be working but it would keep dropping out and I'd lose connection.  Rebooting the Lynksys would bring it back for a  few minutes and then it would drop out again and again.  After chasing every conceivable element of the system from the entry into the house, cables through the rooms and replacing the VOIP boxes, etc. and ready to give up and call in the ISP guys I did one last switcheroo and replaced the coax between the wall outlet and the Lynksis box.  And, as you have guessed by now, replacing the 2ft cable with one that has higher grade connectors did the trick and I am back to 30 mbps download speed.    Just my example for the day.

There is a Dolby digital setup sequence that might have something to do with its passing the digital signals.  Check that out, too.  

I am studying the owners manual and if I get some new insight will send you a follow up.

Good night for now.  

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