stealthjoe wrote on 2024-12-10, 09:42:

I have a S370 board (M6VLR, Via C3 600, 128MB RAM) with the onboard sound chip VIA VT1612A and had installed Win 98. The onboard sound drivers (Via sound system/Avance) get installed without a fuss. However, the problem is that there is absolutely no sound output. Tried doing a clean install as well as doing a fresh install of XP (which should automatically install the sound drivers). The audio output is still missing. There is no visible damage to the audio traces. I am suspecting an issue with the onboard IC.

The attachment m6vlr audio.jpeg is no longer available

Tested the IC and noted that the input voltage is present (5V). While testing the lineout, there is a feedback (popping noise) through the speakers. Could someone please share their experience and thoughts in fixing such onboard audio issues? Thanks.

some motherboards need jumpers set for rear audio, since your board doesnt have the standard header for audio you may have to connect a 4pin speaker to the front panel to get sound out the back, ive got an asus board from an old hp pavillion thats pretty much the same, that doesnt have a standard header only a 4pin connector, and i had to keep the front panel pcb from the case to get sound working out the back.

if its not that it could be the drivers are not much good which is sometimes the case with VIA drivers and AC97 in general, soggi's got some drivers here on his site
https://soggi.org/drivers/via.htm
it also says the drivers are included in win 7, might be worth installing a 32bit version of win7 to see if it produces sound, if not then it may be something else, ive also got a board and it only produces sound from one channel, havent found the cause yet, nothing seems damaged, but sometimes its hard to tell.

My first thought also was the driver, I don't know what "Via sound system/Avance" is supposed to be. The VT1612A isn't the "sound chip" - it's the AC'97 codec, the audio controller is integrated in the VIA VT82C686B southbridge. Because both parts are from VIA, the only appropriate driver is the VIA Vinyl AC'97 driver (DudeFace already posted the link to my website above) - would the codec be from Realtek, you could additionally use the Realtek AC'97 driver.

Be sure that all jumpers are set correctly (like DudeFace said) and onboard audio isn't disabled in the BIOS!

kind regards
soggi

Thanks for the replies. The "Via Sound System" was the one installed automatically in the device manager when Win 98 autodetected the onboard sound. Have also tried the Vinyl AC'97 audio driver, but no luck. The volume icon is indeed present on the taskbar and the "Multimedia" icon has all the required volumes enabled (which shouldn't be the case if any driver issues). Had tried viasbcfg to configure the sound under DOS, but the same result.

As explained earlier, even doing a fresh install of XP couldn't bring sound. Moreover checked for any audio jumpers but couldn't find it on this board. The manual also doesn't state so. The onboard sound chip is enabled in the BIOS. Now it is getting interesting. Is there a possibility of audio controller damage inside the south bridge? or could the AC'97 codec failure cause the audio drivers to install normally but no sound?

if your board is a biostar i did just check the manual again, the speaker on the front header is only for error code beeps and doesnt output sound from the audio system, so its probably irrelevant to your problem, as soggi said try the realtek AC97 drivers, one thing i will say is they can be a hassle to get working, ive got 3 different versions and from what ive found all will install the audio device, but only one will actually produce sound, though i can never remember which one 🤣

A3.41
http://vogonsdrivers.com/getfile.php?fileid=1319&menustate=0

WDM_A398
https://drivers.softpedia.com/get/SOUND-CARD/ … iver-A398.shtml

WDM_A406
https://drivers.softpedia.com/get/SOUND-CARD/ … iver-A406.shtml

you might have some luck with one of these, if not might be better off with a soundcard 😀

stealthjoe wrote on 2024-12-11, 04:42:

Thanks for the replies. The "Via Sound System" was the one installed automatically in the device manager when Win 98 autodetected the onboard sound. Have also tried the Vinyl AC'97 audio driver, but no luck. The volume icon is indeed present on the taskbar and the "Multimedia" icon has all the required volumes enabled (which shouldn't be the case if any driver issues). Had tried viasbcfg to configure the sound under DOS, but the same result.

Never heard of that name and Win98 shouldn't auto detect the audio device because it's newer than it self - that's odd. If everything looks normal, then it's unlikely that there's a chip-defect. Device manager also says that everything is OK with the audio device(s)!? Do you have the latest BIOS flashed? Could you post a high-res photograph of the whole motherboard?

stealthjoe wrote on 2024-12-11, 04:42:

Is there a possibility of audio controller damage inside the south bridge? or could the AC'97 codec failure cause the audio drivers to install normally but no sound?

The first case is very, very unlikely - it might be even electrically impossible that only the audio controller area of the SB's die got damaged AND everything else works fine. The second case is also not very likely, I guess there would be problems with identification when trying to install the driver and even if that wouldn't go wrong, there would be an error message somewhere (f.e. in the device manager).

DudeFace wrote on 2024-12-11, 05:36:

...as soggi said try the realtek AC97 drivers...

No, I didn't say that! I said...

soggi wrote on 2024-12-10, 18:29:

Because both parts are from VIA, the only appropriate driver is the VIA Vinyl AC'97 driver (DudeFace already posted the link to my website above) - would the codec be from Realtek, you could additionally use the Realtek AC'97 driver.

That means:
1. VIA southbridge + VIA AC'97 codec -> you need the VIA Vinyl AC'97 driver!
2. VIA southbridge + Realtek AC'97 codec -> you can take the VIA Vinyl AC'97 driver OR the Realtek AC'97 driver!
3. there are some more combinations with other chipsets and other AC'97 codecs!

For example there's the ECS Elitegroup K7S5A which has an SiS7012 AC'97 audio controller integrated into the SiS 735 chipset - supported by an Avance Logic (Realtek) ALC100P AC'97 audio codec OR a C-Media CMI9738 AC'97 audio codec. If you have the former AC'97, you can take the SiS or the Realtek driver - if you have the latter, you have to take the SiS driver. C-Media itself didn't release generic drivers.

BTW I have also all the latest (generic) Realtek AC'97 / HD audio and Realtek network/LAN drivers on my website -> https://soggi.org/drivers/realtek.htm. I never had a problem with the latest version A4.06 of the AC'97 drivers (on appropriate hardware).

kind regards
soggi

soggi wrote on 2024-12-12, 03:53:

DudeFace wrote on 2024-12-11, 05:36:

...as soggi said try the realtek AC97 drivers...

No, I didn't say that! I said...

yeah ignore that, i missread, i was still half asleep. 🤣

for some reason i usually have trouble with the AC97 drivers, going for the latest one doesnt always seem to work for me, i often find myself trying multiple until i get working sound, though its not always the case.

also funny you should mention the SiS7012, thats the one that was giving me trouble just the other day on a medion MD5000, the 2 different 7012 drivers i tried didnt work, since it has an ALC650 i went for the realtek AC97 drivers and it worked right away, though i was only getting sound out of one speaker, not sure what the cause is, jumpers are set and theres no obvious damage on the board, not worth looking into as im using a sound card, might be OP's best option as well.

also thanks again for the MD5000 drivers on your site 😀

DudeFace wrote on 2024-12-12, 05:02:

yeah ignore that, i missread, i was still half asleep. 🤣

No problem! 😉

DudeFace wrote on 2024-12-12, 05:02:

also funny you should mention the SiS7012, thats the one that was giving me trouble just the other day on a medion MD5000, the 2 different 7012 drivers i tried didnt work, since it has an ALC650 i went for the realtek AC97 drivers and it worked right away, ...

That's why I didn't add the SiS driver to the OEM MSI MEDION MD5000 Ver:1.0 (MS-6701) spec page (same f.e. with AOpen s661FXm-FSN) - the Realtek drivers are better and newer. On the K7S5A spec page I had to add them for the ones equipped with the C-Media AC'97 codec.

DudeFace wrote on 2024-12-12, 05:02:

... not worth looking into as im using a sound card, might be OP's best option as well.

I would still try to look for the reason but yes, if there's no way, I would also consider to add a sound card.

DudeFace wrote on 2024-12-12, 05:02:

also thanks again for the MD5000 drivers on your site 😀

You're welcome! 😀

kind regards
soggi

Maybe, take a look here if you didnt https://download.viatech.com/en/support/driversSelect.jsp

I think that the page is easy to understand.
The VT1612A seen ro be a Vynil audio, I guees the Sourhbridge is a 686A or B, doesnt have anything related to Realtek.

Hoping:

The Realtek thing has been clarified already and links to drivers have been already posted! Didn't you read the posts?

DudeFace wrote...

DudeFace wrote on 2024-12-12, 05:02:

yeah ignore that, i missread, i was still half asleep. 🤣

kind regards
soggi

soggi wrote on 2024-12-12, 16:30:

Hoping: […]
Show full quote

Hoping:

The Realtek thing has been clarified already and links to drivers have been already posted! Didn't you read the posts?

kind regards
soggi

Ok, easy, no problem, I read the posts, I only added the link to the VIA page because I found it interesting, I didn't see it in any post, unless I missed it.
Nobody is perfect.

It's better to read the posts carefully before posting. 😀

DudeFace already posted a link to my website's VIA driver page (https://soggi.org/drivers/via.htm) where the latest version is available from.

On VIA's website - which was also partially offline and moved between places in the past - you have several confusing options which even don't show the latest driver version. F.e. if you chose Step 1. "Microsoft Windows", Step 2. "Windows 98SE" and Step 3. "Audio", then you have the choice with Step 4. (see screenshot below). I never would recommend this link of VIA's download portal to any "normal" user because you will be lost in an unsorted heap of old driver versions.

kind regards
soggi

Interesting, maybe both Nvidia and AMD and others should rethink how their websites work, because the system used on the VIA website is quite similar to the one used by almost all manufacturers for many years. For me, and I guess, many others, it is a normal system.
And the issue of having different versions older or newer... it is quite clear in this forum that the latest versions are not always the best. Having read this forum, the examples are quite a few., Nvidia 45.23, and the different versions of the VIA 4in1 drivers that work best or worse, depending on the chipset, although even the latest version of the Hyperion drivers supports almost all VIA chipsets.
And, learning these things is part of the fun of this hobby.

soggi wrote on 2024-12-12, 03:53:

Never heard of that name and Win98 shouldn't auto detect the audio device because it's newer than it self - that's odd. If everything looks normal, then it's unlikely that there's a chip-defect. Device manager also says that everything is OK with the audio device(s)!? Do you have the latest BIOS flashed? Could you post a high-res photograph of the whole motherboard?

Please see the IRQ 7 allocation for the onboard device :

Also below are the board pics:

I also did notice a small trace damage at the bottom part of the board near the ATX socket. However, I doubt if it is actually connected to the onboard audio circuit:

Update:
I tested the caps around the audio codec IC as well as one between the ATX connector and the gamport output using a dedicated capacitance meter. One 22uF cap measured at 40 uF. The next 22uF cap was 4 uF. The final 22uF cap was around 5 uF. One 100uF capacitor was 4 uF. All other caps around the audio circuit looked to be within the tolerance (+/- 10%). Wondering if this has something to do with the complete lack of audio output?

stealthjoe wrote on 2025-01-13, 10:20:

Update:
I tested the caps around the audio codec IC as well as one between the ATX connector and the gamport output using a dedicated capacitance meter. One 22uF cap measured at 40 uF. The next 22uF cap was 4 uF. The final 22uF cap was around 5 uF. One 100uF capacitor was 4 uF. All other caps around the audio circuit looked to be within the tolerance (+/- 10%). Wondering if this has something to do with the complete lack of audio output?

Did you test them out of circuit though? Most of the time this is necessary to get a valid measurement.

It's not uncommon for that chip to fail in such a way that on software side everything works fine while there is no analog output. The chip has integrated headphones amplifier whose output is often used by the motherboard and traced to the green plug. In that case there is nothing you can do except changing the whole chip. Now, how to check whether it is the chip or something else. You can make a wav file, for instance generate a sinewave of 1kHz, play that file in loop and check some output pins. Oscilloscope would be great but a multimeter can also help. Pins 39 an 41 are headphone amp out and there should be a signal. Pins 35 and 36 are line out and there should be signal even if headphone amp failed inside the chip. On pin 48 there is a SPDIF digital output which also should gave digital output which can be sent to a external dac practicaly with just two wires. If you can measure the signal at those outputs then there is a problem in external components between the chip and the plugs.

kokerich wrote on 2025-01-17, 12:32:

It's not uncommon for that chip to fail in such a way that on software side everything works fine while there is no analog output. The chip has integrated headphones amplifier whose output is often used by the motherboard and traced to the green plug. In that case there is nothing you can do except changing the whole chip. Now, how to check whether it is the chip or something else. You can make a wav file, for instance generate a sinewave of 1kHz, play that file in loop and check some output pins. Oscilloscope would be great but a multimeter can also help. Pins 39 an 41 are headphone amp out and there should be a signal. Pins 35 and 36 are line out and there should be signal even if headphone amp failed inside the chip. On pin 48 there is a SPDIF digital output which also should gave digital output which can be sent to a external dac practicaly with just two wires. If you can measure the signal at those outputs then there is a problem in external components between the chip and the plugs.

Thanks for the details. I tried testing the continuity of the pins but with the board switched off. Tested the continuity between the pins 35 and 36 and the Line out plug (green), but there was no beep. However, with the analog ground pin 26 and the ground of green plug, I was indeed getting the beep. Similar case with analog ground 2 (pin 42). So to sum up only the ground pins are showing continuity across the circuit. So to test the ic outputs alone with a multimeter, my understanding is that it needs to be done for eg. with left channel, one probe is to be on pin 35 (analog left) and other probe on pin 26 (analog ground 1). Similarly with pins 36 and 26. Please let me know. Thanks!

The ground is common (reference) to all signals so it is normal to show continuity across the board, if there are resistors between plugs and signal pins it is normal not to hear beep since most multimeters beep if resistance is below 50 ohms, you can try on 200 ohm, 2k or 20k scale to see what is the resistance, if the resistance is infinite there is no connection. My hunch is that green plug is connected to pins 39 and 41 because some motherboards wanted to drive headphones directly without additional amp. Sometimes if headphones' cable/jacks are faulty they may short the out to the ground and damage the on-chip amp, hence no output. For testing channels with multimeter put one probe on analog ground (black) and the other (red) on signal pin (35, 36, 39 or 41), set it on the ac voltage mode 2V (depending on the volume setting the signal is usualy several hundreds of mV). If you are playing something you should be able to read it out on multimeter.

kokerich wrote on 2025-01-17, 16:12:

The ground is common (reference) to all signals so it is normal to show continuity across the board, if there are resistors between plugs and signal pins it is normal not to hear beep since most multimeters beep if resistance is below 50 ohms, you can try on 200 ohm, 2k or 20k scale to see what is the resistance, if the resistance is infinite there is no connection. My hunch is that green plug is connected to pins 39 and 41 because some motherboards wanted to drive headphones directly without additional amp. Sometimes if headphones' cable/jacks are faulty they may short the out to the ground and damage the on-chip amp, hence no output. For testing channels with multimeter put one probe on analog ground (black) and the other (red) on signal pin (35, 36, 39 or 41), set it on the ac voltage mode 2V (depending on the volume setting the signal is usualy several hundreds of mV). If you are playing something you should be able to read it out on multimeter.

I proceeded to test the pins. First measured the resistance between the line out (green) socket and pins 35/36. It was around 3.5 mega ohms. Also did measure the resistance between the green socket and pins 39/41. It was similar at around 2.5 mega ohms. Then switched on the board and measured the AC voltage between pins 35/36 (line out L and R) and 26 (ground) by running the 1Khz sound file. There was hardly any output voltage across both the pins. Similarly tested the pins 39/41 against 42 (AGND2). It was the same case. The voltage seemed to climb to 2V for a fraction of a second and then it reduced to 0.002V while the sound file played.

One more observation I noted was that despite the installed sound drivers not showing any errors, when I play an audio file, it seems to stall within a few seconds. Similar is the case with the 1Khz file. It plays fine for around 4 seconds and then slows down considerably. Similarly when playing any one of the files under "Sounds Properties" icon in Control Panel, the play button is never enabled again after any of the sounds start playing. Below is the image of what I am referring to:

Now I am starting to think if there is indeed an issue with the IC as there was close to 0V at the line out (35/36) pins as well as the headphones line out (39/41) pins.