Originally Posted by TivoCommunityAR
Have a Roamio Plus connected to Marantz SR7008 receiver via HDMI.
When I have the TiVO Dolby in use I get an annoying mechanical click in the receiver whenever I skip forward or backward, and other times like when some commercials play or I change channels. I presume this is when there is an interruption in the Dolby audio.
To get rid of the click, I can set the Roamio for "PCM only (no Dolby)" in the audio settings. The Marantz also has a decode option in the Inputs menu for "Auto", "DTS" and "PCM" that I just left on Auto.
Question: Isn't "Use Dolby Audio" better than "PCM only (no Dolby)"? If Dolby is better, is there any way to "Use Dolby Audio" instead of "PCM only (no Dolby)" on the Roamio and not have the mechanical click in the receiver all the time?
Question: So what is the real difference between "Use Dolby Audio" and "PCM"? The receiver says, "Dolby D" on the display with the Tivo set to "Use Dolby Audio" and "PLIIx" with PCM. Both have what looks like a Dolby icon on the receiver display.
Dolby Digital or Dolby Audio, as you described it above, is a discrete 5.1 channel audio format, and is part of the HD broadcast standard. If you pass this signal to your receiver, the receiver decodes it, and outputs discrete 5.1 audio. PCM, in the case of TiVo, is 2 channel only. TiVo down-samples the Dolby 5.1, and outputs it via PCM, so yes, Dolby 5.1 is "better". Someone correct me if I am wrong regarding the downsampling - maybe there is a two channel standard in HDTV, but I didn't think there was.
When you send PCM audio, from a TiVo, you will see the Dolby PLIIx2 logo on your receiver - Dolby PLxII2 is "converting" the 2 channel stereo into either 5.1 or 7.1 sound (depending on your receiver settings and speaker setup). From what I understand (I don't use it too often), it does this pretty well, and is mostly center channel focused.
Have you compared the two? Which sounds better?
I don't know of a way to get rid of the relay clicks in your receiver when using DD from a TiVo (or any source where the 5.1 signal is interrupted).
What model of TiVo do you have? I am wondering if TiVo has added passing the DD 5.1 audio via PCM in any of the Roamio models?
Does anyone know why TiVo down-samples 5.1 audio to 2 channel audio when using PCM?