music via spdif?

[johnsonx42]

yes, I meant the MPEG1 decoder - disabling it has always solved the stuttering audio problem, but it wasn't a usable solution since I have analog channels too.

And YES! the <ForcedLiveTVClock>AC3 Audio Renderer</ForcedLiveTVClock> setting corrects the problem completely... thank you! I've been watching LotR:Return of the King on StarZ for the past 45 minutes, and the audio sync is still spot on. It was unwatchable before.

I had previously tried a registry setting PreferAC3=1, but that didn't help, it probably solves a different problem.

This thread has been most fruitful!

[johnsonx42]

and now of course I have stuttering and audio drop-outs on channels with MPEG-1 audio. Can't win.

[whurlston]

CTRL-E then select the mpeg-1 audio track and it should change the clock reference. Not sure if there is a remote button for audio track selection.

If you have more channels with MPEG-1 audio, you can set config.xml back to "Default" and use CTRL-E for AC3 channels. All of my channels are AC3 so I force the clock to that.

[mvallevand]

I use the PreferAC3 registry setting and it works well for sync I think the nuance is it sets the LiveTV defaults to AC3 instead of m2a but the synce changes when m2a is found. I use LAV or ffdshow for AC3 and Microsoft for m2a and it is all working well for sync.. It seems only NextPVR users are using AC3filter these days, not sure why it is so popular here.

Martin

[johnsonx42]

when I had the <ForceLiveTVClock> set to Default I did notice that reselecting the AC3 track 1 would reset the audio back into sync, but it would drift behind again within just a few minutes. I'll try the reverse as suggested by whurlston. I'll also try different decoders; in the past AC3Filter was the only one that didn't give me sync issues, but maybe combined with the TVClock and PreferAC3 settings I can get others to work.

This still seems like some sort of bug in NPVR... my channels all have either MPEG-1 or AC3 audio, none have both that I know of, so why can't NPVR get the clock reference right?

[johnsonx42]

yet another question, only tangentially related to the original title of this thread... I've barely joined the 21st century when it comes to digital audio.

When I configure the Digital audio output in Windows, there's a tab titled "Supported Formats". When I test Dolby Digital, it works fine - sound from the speakers, and the Dolby Digital indicator lights on the receiver. However when I click on DTS and test, I get no sound, and nothing appears on the receiver's display. Yet the receiver has a DTS logo on it, the manual says it can decode DTS and indicates that a DTS indicator will appear if it detects a DTS signal.

Any idea why DTS doesn't work for me? I've tried with both the generic "Microsoft High Definition Audio Device" that Windows 7 installed by default, and the latest Realtek HD Audio driver from their site. I tried various google searches, but could only find people saying some particular app wouldn't generate DTS audio after they'd tested it successfully and enabled it in the same "Supported Formats" dialog, which is obviously a completely different issue.

[thisheat]

At the risk of stating the bleedin' flippin' obvious, do you have a DVD/BD player you can use to test DTS? It would be good to take the receiver out of the troubleshooting equation.

I've heard that DTS is more vulnerable to sync issues than AC3, but personally haven't had that problem. You can also try allowing DTS passthrough in AC3Filter config->SPDIF. You never know...

Oh, and don't feel bad about just now joining the 21st century. For music at least, the best sounding receiver I've ever had was made in the early 70s.

[mvallevand]

Actually SPDIF is 20th century, it doesn't have what it takes for 21st century HD audio. Many say it is simply because of bandwidth, but a lot of factors are in play.

Martin

[thisheat]

What's the preferred method today? HDMI 1.x?

What kind of factors, and what do you use? I'm still pretty 20th century myself, so I'd love to hear from someone who's up to date with the latest and greatest.

[mvallevand]

To consider that I am current is odd since when I look at my neighbor's McIntosh tube system it still makes me envious. I remember buying a satellite system in '82 so that I could watch MTV yes it did play videos then and more specifically to listen in stereo those wer two things that were impossible here in Canada at the time. MTV got me their commercials that listening through the TV was like listening to a "manacled gnat". I went rear channel Dolby in the 90's and 5:1 about a decade ago and although I am now DTS-HD capable I won't be 7.1/2 until next year and I don't consider it a big deal since I watch pretty much only recorded broadcast TV and listen to 2 channel music.

To go full circle in those thirty years, both my wife and I found the sound quality on the MTV VMA's this weekend so awful that we turned all these gadgets off and listened through the TV. We probably should have just changed the channel but that's another story.

Martin