No Audio from HD Channels (SAF 5.0) (1 Viewer)

finrudd341

Portal Pro
February 24, 2008
208
16
Sao Paulo, Brazil
Home Country
Brazil Brazil
MediaPortal Version: 1.1.0 RC1
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Windows Version: Windows XP Pro SP3
CPU Type: Intel Core 2 Quad Q6600 Processor
HDD: 3 x Wester Digital WD10EACS 1000Gb (RAID 1) & 1 x Wester Digital WD1600Js 160GB boot drive
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Motherboard: Asustek P5E-V HDMI L775 Motherboard
Video Card: Intel G35 Express Chipset
Video Card Driver: 6.14.10.5016
Sound Card: Realtek High Definition Audio
Sound Card AC3: Coaxial out to AV Receiver
Sound Card Driver: 5.10.0.5404
1. TV Card: Generic Philips SAA713x Hybrid Capture Device (ISDB-T + Analogue)
1. TV Card Type: ISDB-T & Analogue
1. TV Card Driver: 1.345.9.603
2. TV Card: Digital Everywhere FireDTV BDA
2. TV Card Type: DVB-C
2. TV Card Driver: 4.8.0.0
MPEG2 Video Codec: SAF v5 pack
MPEG2 Audio Codec: SAF v5 pack
h.264 Video Codec: SAF v5 pack
Satelite/CableTV Provider: NET TV (Brazil)
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Power Supply: ZM600-HP Heatpipe Cooled 600W Modular PSU
Remote: Microsoft MCE standard
TV: Sharp Aquos 42"
TV - HTPC Connection: G35 HDMI to TV

This is a strange one, and I am just not finding a solution :(

My SD TV channels all have audio and video, but my HD channels (broadcast in H264) all start with a burst of audio, perhaps less than half a second, and then nothing.

The ffdshow is saying it as:
Input 48000Hz Stereo, PCM (uncompressed)
Output 48000Hz Stereo, 16-bit integer

There is one HD channel where audio works, and while the video is broadcast in H264 still, the audio is:
Input 48000Hz Stereo, mp2 (libavcodec)
Output 48000Hz Stereo, 16-bit integer

With the SD channels, the input and output are as follows:
Input 48000Hz Stereo,
Output 48000Hz Stereo, 16-bit integer

Attached are screen shots, the ffdshow export, and the Realtek Audio setting for the SPDIF output (set to 48000Hz)

IN summary - the audio seems to work on most channels when it is mp2 (libavcodec) as an input, but when it is Stereo PCM (uncompressed) as input, it doesn't work!

Any thoughts please, or any other information I can provide to help troubleshoot? Audio in all other applications and movies works fine. :D
 

Attachments

  • ffdshow output settings.jpg
    ffdshow output settings.jpg
    112 KB
  • HD No Audio.jpg
    HD No Audio.jpg
    98.4 KB
  • Realtek HD Audio.jpg
    Realtek HD Audio.jpg
    77 KB
  • ffdshow.zip
    16.9 KB

finrudd341

Portal Pro
February 24, 2008
208
16
Sao Paulo, Brazil
Home Country
Brazil Brazil
OK - so there's some confusion on my part here...

When previewing the channels via TV Server Config, ffdshow is used for both audio and video it seems. When actually watching the channels, the MP client settings take over, and then the Monogram decoder is used for TV with LATM AAC Audio in the broadcast. So, this is unrelated to ffdshow I think - however, audio does not work for ffdshow or Monogram on most of my HD channels.

This has at least shown me there is a difference in how ffdshow sees the audio type between my channels that work, and those that don't. Through ffdshow I was able to see that the audio that works is mp2 (libavcodec), but Stereo PCM (uncompressed) doesn't work.

Is there any way I can view what Monogram is doing with the audio in a similar way as I can with hovering my mouse over the ffdshow icons?

Lastly, someone has suggested that this might be a problem with how Brazilian TV is broadcast - there is a modified version of Monogram (attached) which addresses this, and the mod author is trying to get the Monogram author to review and include it in the original code. Attached for anyone who can look at this and say 'Ah! I know what your problem is...' :D

Summary: ffdshow is showing exactly the same signs as Monogram - short burst of audio when selecting the channel, and then no audio until changing to a non-HD channel that uses mp2 (libavcodec). I have not yet discounted signal strength being an issue.

FIXED!

Ok - the problem related to how the audio is broadcast with ISDB-TB here in Brazil, and DucaSP kindly pointed me in the right direction. Specifically, it relates to the sbr signaling, and there is a modified version of the Monogram Decoder available. I updated the mmaacd.ax files on the computer with the mod'd version, and audio now works perfectly on all of the HD channels - probably only relevant to Brazil, but might be relevant in the future to other countries adopting the ISDB-T standard, which is most of Latin America now.
 

Attachments

  • mmaacd.zip
    917.5 KB

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