Realtek ALC650 SPDIF - Light but no sound output! RRS feed

  • Question

  • OK..

    This one has got me pulling my hair out!! I hope you guys can help.. I'm surprised I havent found anyone else in my boat out there!

    I have a little Shuttle G2 6100H PC, also known as the SB61G2v3.  It has the FB61 v3 motherboard made by shuttle themselves and an onboard Intel Springdale 865 chipset. More importantly, it has SPDIF in and out and uses the Realtek ALC650 AC'97 audio codec with the Intel ICH5 chip for onboard audio. Also, I am running Vista Home Premium. I'm running the latest chipset drivers and latest drivers for vista from realteks own website.

    Now here's the problem..

    I have hooked up my amp with optical input to the Shuttle's optical out via an SPDIF compatible optical cable. The red lights shines through it just as it should and connects fine at either end. In Vista, I selected 'Realtek Digital Output' to be the default output and when I click to hear the test sound, I see the green bars bouncing but hear nothing at all, absolutely nothing!

    Now, I checked over all the obvious, I checked the same cable and used it to connect my laptop to the amp via SPDIF and no problem, everything was perfect. That rules out amp settings/cable problems. I even played around with different settings on the amp, like stereo, auto, 5.1 etc, no change. I checked all menus in Vista for levels/muting found nothing stopping it. Set up media center with spdif settings to see if that would output anything but nothing. It is probably worth mentioning at this point that my normal stereo output via 3.5mm jack is absolutely fine.. this is what is also intereting, I connected my laptop via SPDIF to the SPDIF in on the shuttle and that works fine, I can the hear sound through my analogue jack so that means its just the SPDIF output that is giving me the shits!!!

    What I dont understand is that, why does it emit the light if it is not sending anything? Surely also this means that it is not a faulty connection on the motherboard.. the only thing I noticed that might be of concern is that once installed, Vista or the Realtek drivers name the SPDIF input as being SPDIF but the output as being 'Realtek Digital Output.' I'm just wondering, had this been named SPDIF too it might work like the input! I'm guessing its because of duplicate names..

    So anyway.. I'm surprised nobody else has had this issue.. maybe its just because I'm the only one trying SPDIF on this particular board in Vista.. but any ideas?? I'm now officially desperate!!


    Friday, January 18, 2008 12:25 AM


  • Hi,


    Thanks for your question.


    I would like to suggest that right click on the speaker icon in the Notification Area of the Taskbar and select Playback Devices. If you do not have speakers that can accept a digital input (SPDIF), then set Speakers as your default.

    Also, in the Playback Devices window, right click and select both Show Disconnected Devices and Show Disabled Devices. And while you are there go through the Configure and Properties buttons to configure your devices and on the Sounds tab test your setup.


    There is a KB article may be helpful, for your reference:

    An audio device outputs PCM audio instead of DTS audio from the S/PDIF connection in Windows Vista


    Also, I would suggest that contacting the manufactory for technical support at the same time to confirm about driver. Because this issue may depend on both hardware and software behavior.


    Guozhen Wang
    Microsoft Online Community Support

    Thursday, January 31, 2008 7:11 AM