AC3/DTS "cuts" SPDIF signal on Zotac ION N330

Hi there

First of all, let me say, I am a total linux beginner, so if you can help me with the following problem, please be as specific as possible

I've recently bought a Zotac ION 330, I have been using windows XBMC for quite some time now on my old HTPC, but since there is no support for GPU acceleration i had to change to linux (ubuntu).

With some help from my some of my linux experienced mates I was able to setup Ubuntu with XBMC and pretty much everything is running as it should

But I have run into a problem I havent been able to find a solution for on the forums nor on the wiki.

Problem:
When playing AC3/DTS content, once in a while (every 5 min or so) the SPDIF signal cuts for <0.5 seconds and then resumes as it should. It is not a lot, but it is enough for me to notice and therefore: be annoyed by it.

I havent been able to reproduce this problem on 2ch MP3 audio content(PCM). Its only on AC3/DTS

My system spec is as follows:
Hardware: Zotac ION N330, 1 GB ram
Linux Distrobution: Ubuntu 9.04 - 2.6.28-15 Generic 32 bit - Up to date as of 2009-10-04(from the "uname -a" command)
Architecture: i686
Install Method: PPA
SVN Revision: 23321 (I have also tried with 23281, where the problem still is present)
Nvidia driver: 185 (From nvidia.com)
Sound: Updated to version 1.0.21 using the ALSA update script

Besides that, I have tried removing Pulse-Audio as well as only enabling the External audio (Realtek ALC662) in bios.

Any help will be much appreciated, I am a bit lost atm

Hi,
I've got the same problem. Dont know if it's only with ac3 or anything.
Also everytime I start a movie or music it takes some time (1 sec.) before the sound is turned on.
Doesn't matter if it goes over the hdmi or over the spdif?

Anyone yet?

i'm having the same issue since i upgraded my AMP, noticed it on dts movies, will try ac3 later. Every 75 seconds +-3

yesterday i have the same problem while watching a 1080p Movie over HDMI.

Every ~5-10 Min. the Audio Signal lost and returns. (~1second)

Bug in Xbmc?


Thanks!

(HW: AsRock ION 330)

i reaquired my old AMP to see if the problem is there too, i will have time later today to test it out.

what AMP are you guys using?
mine is a yamaha 465, i read on the internet that it might have a bad error correction if the ac3/dts stream jitters during playback.

Sony STR-DG820, but i dont think that can be a problem with the AMP because my HDX1000 and WDTV plays all stuff without these audio "lags".

I think that must be an Bug in Linux/Xbmc/Alsa I don't know.

Hope anybody can help us

I have the same problem on my Asrock ion 330.

I am not sure it fix this problem to 100% but you could try to use a .asoundrc file with dmixer. There is a sample in another thread discussing this problem.

I used that file to fix the problem with shutter/spikes when opening e.g. a dvd iso using spdif with passthrough to the amp. This problem was fixed.

@vikjon0: i tried to find the thread you are refering to, can you please point us at the right one?


one thing i found out, if playing a dts movie the @24p the sound drop occours every 115 seconds +-2

the sound drops on DTS is more noticeable (sound really gone for a fraction of second), on ac3 its even less fraction of a second so not as much noticeable.

can you confirm that?

For me its very different, not every 115 seconds.

I try now the reproduce these Error and take a look in the xbmc.log file in the /home/<username>/.xbmc/temp/ directory.

What says your xbmc.log file, after the error comes up