Sound Stuttering/Clipping on HD Stations only

[charli181]

TV-Server Version: tvEngin 03 16429
MediaPortal Version: 2.3.0 rc3 svn 3-11-07
MediaPortal Skin: XFace 1.2
Windows Version: WIN XP SP2 (Client)/Win 2003 Server (TVServer)
CPU Type: AMD 64 +4800 (Client)/Intel DualCore 2150(Server)
HDD:
Memory: IGB DDR2 800(Client)/1GB DDR2 667 (Server)
Motherboard: Asus M2A VM-HDMI(Client)/GigaByte GA-VM900M (Server)
Motherboard Chipset: AMD 690G
Motherboard Bios:
Video Card: Integrated ATI Radeon X1250-based graphics
Video Card Driver: Catalyst 7.2
Sound Card: ALC883 High Definition Audio 6-channel
Sound Card AC3: Coax out
Sound Card Driver:
1. TV Card: Twinhann DVB-T
1. TV Card Type: DVB-T
1. TV Card Driver:
2. TV Card: Leadtek DTV-1000T
2. TV Card Type: DVB-T
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec: FFDShow
MPEG2 Audio Codec: AC3Filter
Satelite/CableTV Provider:
HTPC Case:
Cooling:
Power Supply:
Remote:
TV: Sony 40" LCD
TV - HTPC Connection: Sub-d & HDMI


Whenever I select a HD Channel here in NSW Australia, the sound is selected as AC3 and I hear sound. The problem is that it sometimes disappears for half a second, in which time my Amplifier then re-syncs to prologic. If this happens frequently (many times in a few seconds) the sound disapears and I have to stop and start the stream again.
Second issue is when listening to the HD channels, it seems to be clipped or flutterery. The picture is smooth with no dropped frames or pixelation from poor recption so it seems is just the sound that is having a problem. I am runnning my sound as SPDIF passthrough so no decoding is done by the PC. SD Channels are working superbly and the AMP even shows it as an MPEG stream.

What I have done so far :-

Updated Realtek Drivers to latest
Tried all the different settings in AC3 Filter 1.46 - One at a time
Tried SPDIFER (10/2007) with all the different setting
DVD's running Dolby DIgital or DTS run perfectly with no sound quality issues. These are stored on DVD Disks or a Hard drive on the network

What other things can I try to deduce where the fault lies.

[erosco]

Charli181,

I had a very similar problem on my M2NPV-VM motherboard with a similar setup. I found that changing the Audio Renderer (either in the configuration program or under Settings, My TV, Audio Renderer) to Default Directsound Device or to DirectSound SoundMAX Audio 0 solved the problem.

[charli181]

I Give it a go erosco. Currently set to Default Directsound device, adn windowsXP has been setup accordingly to use the SPDIF output as the default out. I will try selecting the card output direct to see if this helps.....

[charli181]

Originally Posted by erosco

Charli181,

I had a very similar problem on my M2NPV-VM motherboard with a similar setup. I found that changing the Audio Renderer (either in the configuration program or under Settings, My TV, Audio Renderer) to Default Directsound Device or to DirectSound SoundMAX Audio 0 solved the problem.

Thanks Erosco but that did not help either, has anyone else got some ideas on how I can fault find this annoying problem.