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Discussion Starter #1
Pulled out an old classic favorite off the DVD shelf last night, the original House of Wax with Vincent Price, and when the disc loaded and began to play the Warner Bros. intro screen, my Onkyo 605 didn't recognize the Dolby Digital signal coming from the DVD, thus there was no small orange "Dolby" logo on the display of the AVR where it normally is. As the disc's main menu loaded up, I selected the language as usual, pressed PLAY MOVIE, and the film started with STILL no orange Dolby Digital light on the display...

As I moved closer to the AVR, I noticed the display screen was reading "PCM" as the incoming signal, indicating there was suddenly no bitstream signal coming from my BD player (connected over HDMI to the 605) and yet I was getting sound from the DVD -- BUT, in my Oppo BD player, I do not have ANY codecs set to transmit PCM data...ONLY bitstream (HDMI Audio is set to BITSTREAM and two-channel digital sources are set to drop into the "Pro Logic II MOVIE" mode under the Listening Mode menu of the Onkyo). Very, very weird because I have not touched ANYTHING in either the player or AVR for this switch of incoming signal and processing to occur...

I ended up stopping playback of the disc (which NEVER gave me problems before) and powering off both the Blu-ray player and receiver, which seemed to fix the issue as when I powered back on, the AVR's display was indeed showing the incoming "Dolby Digital" signal indicated with the little orange light (so the display read "DVD/PLII Movie" with small "HDMI" and orange "Dolby Digital" indicators above the mode reference which I know is the correct way for the AVR to display what's going on).

Has anyone ever experienced this, and why did it happen? How could my player or receiver suddenly "misread" the incoming signal like that without me touching ANYTHING in any of the menus? In other words, instead of my AVR indicating an incoming bitstream Dolby signal, it indicated the audio was coming via PCM which seemed impossible to me because my player is not set up to transmit LPCM signals over HDMI -- the system seemed to do this on its own, and the only way I could correct it was to shut off both the AVR and player...

Really weird.
 

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It sounds like something just got messed up in the "audio handshake" I would not make it out to be an issue, more a glitch that probably wont happen in a long time again. Even though your bluray player may not have anything set to play PCM it could very well have just got confused and downconverted the signal.
 

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According to the WB site, the disc only has Dolby surround stereo; that would show as PCM on an AVR.

Another thought (if it's a different disc):
Given the age of the film, the AVR "saw" a mono signal. Assuming that it actually was not getting a PCM signal (not impossible; there are even 5.1 PCM discs) perhaps the mono signal "confused" the AVR??
 

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Discussion Starter #4
It sounds like something just got messed up in the "audio handshake" I would not make it out to be an issue, more a glitch that probably wont happen in a long time again. Even though your bluray player may not have anything set to play PCM it could very well have just got confused and downconverted the signal.
As always, thank you Tony. :T

I pretty much chalked it up to a "glitch" or HDMI issue, as audio dropouts after handshaking with BD's have happened with this setup, but I just found it strange that it happened with a standard DVD and that it was transmitting a PCM signal from the BD player...

Here's the thing, though...why would I get audio at all even if it was a handshake error if in the BD player setup menu I have all audio set to pass as bitstream?
 

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What Gary says makes sense, if its only a stereo signal it would be PCM
 

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Discussion Starter #6
According to the WB site, the disc only has Dolby surround stereo; that would show as PCM on an AVR.

Another thought (if it's a different disc):
Given the age of the film, the AVR "saw" a mono signal. Assuming that it actually was not getting a PCM signal (not impossible; there are even 5.1 PCM discs) perhaps the mono signal "confused" the AVR??
ALL audio information encoded on DVD's (for the most part) are in the DOLBY DIGITAL format (unless they're specifically prepared in DTS) -- this doesn't matter if it's MONO, STEREO or 5.1 DISCRETE. So when I play DVD's that have "stereo" soundtracks, my receiver processes these as DOLBY DIGITAL STEREO and engages the PRO LOGIC II MOVIE mode (as I have it set to) but STILL, these discs are presenting a DOLBY DIGITAL signal regardless of channels on the disc.

Every DVD I play -- unless they carry DTS tracks -- illuminate the DOLBY DIGITAL orange indicator on the front of my AVR, that's why I knew something was off when I saw PCM. The problem was not the soundtrack, but the way the player was sending out the audio signal; it was, like Tony suggested, as if the receiver or BD player got "confused" and that never happened in my setup before.
 

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Discussion Starter #7
What Gary says makes sense, if its only a stereo signal it would be PCM
Tony,

EVERY audio track encoded on a DVD (unless they are prepared with DTS mixes) carries a DOLBY DIGITAL signal -- it's the way the sound is "baked" into the encode. So, it does not matter if a film has a MONO, STEREO or MULTICHANNEL mix...if it's on a DVD, it's coming over in a DOLBY DIGITAL substream...

In other words, when I play titles with 2.0 STEREO or SURROUND tracks -- such as House of Wax -- the soundtrack may in fact be two-channel stereo, but the receiver still "sees" a DOLBY DIGITAL signal...from there, the AVR applies whatever surround mode I have chosen to apply to these signals (i.e. PRO LOGIC II MOVIE). But the DOLBY DIGITAL indicator still remains on the display of the AVR -- that is with ALL DVD's that don't have DTS soundtracks.

The ONLY way the AVR should indicate a PCM signal is if I instructed the PLAYER to output audio over HDMI to go LPCM, not bitstream, which I have not...which is why it is so weird that the AVR was showing PCM last night, hence the point of my thread...:unbelievable: :gulp:
 
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