Vista generation audio

I'm flabbergasted, so I'm starting a new thread about this. In everything mentioned here, the OS was Vista, but I'm not sure that this is the problem.

I have an Acer Aspire 5102 laptop. AMD Turion 64 dual core processor, and Realtek 'soundcard'. 1gig RAM.

When I play a wave file 100 seconds of 44.1, 16 bit 1.4kHz -6dB stereo tone at low level it plays fine through the on-board audio device using Windows Media Player.

When I play the same tone at higher volume, there are various problems as the level is changed. These include:
1. Audible gaps in the tone
2. The Media Player application becomes unresponsive
3. The Media Player can be closed, but audio continues to play.
4 . Other functions such as the software audio level control cease to respond

The audio level alters which of these problems is at the most critical, but playing tone at moderate to highish level always reveals serious problems.

If I load the same file onto a usb memory stick, at the same levels the semi-lockups occur, but the audio plays without gaps.

Music played through the same machine has audible clicks and some glitches but might be acceptable for casual background noise, although not for any serious listening except at low level. Processor usage rises when the gaps occur. I have searched for but not found any strange audio settings, such as echo cancellation.

Today I visited a local branch of a chain-store, where the sales manager took my usb 'stick' and loaded my file onto 3 machines, only to discover that they all behaved exactly the same with varying degrees of the 'gaps' depending on the level.

The machines were:

Acer Aspire 5051 single core Turion  Realtek HD audio
HP Pavilion D       dual core Turion
HP DV9340         dual core Intel with 2 gigs ram. Connexant audio

What amazes me is that I have seen no reports of this anywhere.

Having removed a load of dross software, an Edirol UA-20 seems to perform OK on the Acer machine.

Running Ubuntu Live on my laptop has audible glitches.

I would be interested in any suggestions as to what to do next. I know that these days laptop audio is not designed for anything more than voice chat, but UI lockups and audible gaps surely cannot be acceptable. I still think there might be some bizarre setting somewhere that I haven't found.

I would be interested in any suggestions as to what to do next.

There have to be more things to do that will isolate what's causing this. Because at present, I'm at a bit of a loss to explain why an increase in the volume level (I presume that's exactly what we're talking about) would cause glitches unless the power supply was so screwed that it was only just running the machine. And on three or four different machines, I'm sure that's not the case at all. First off, I think you need somebody with an identical machine to one of the ones you've tried this on, only running XP. I have a Pavillion, but it's not the same one you used, so that wouldn't be a fair test. I'm pretty sure that if you play MP3s through the internal speaker, it doesn't do that when you turn the volume up, but I'll check anyway.

At the moment, the common ground does look like the OS, doesn't it?

Yes, we are talking about an increase in the volume level. In my day, what happened when you turned the volume knob clockwise. It's surprisingly hard to explain this to computer people.

I've been trying the Ubuntu Live on this machine more thoroughly, and it is much better than Vista. With Ubuntu, I do have horrid glitching and some gaps when the audio is first played, but after the 2 player apps have settled down I hear occasional clicks on the tone at high level and pure tone at lower level. So this is still a little inconclusive.
I've looked through some of the Ubuntu logs, but can't see any mention of audio drivers being loaded. I'm very inexperienced with Linux, though.

I'm wondering if it's possible to load and run XP on a 4GB usb memory stick on my Acer without interfering in any way with the Vista on the C drive. If it's possible, can anyone point me to any advice, warnings or instructions? I've already got emails from Acer support majoring on other OS's invalidating the warranty.

I really need to spend some time reading up about the new Microsoft audio model. I've seen a lot of vague theory and the video from Microsoft with the dire sound, but little direct information about how the hardware/firmware of the on-board stuff actually works. I'm probably too old to understand it anyway.

I'll keep asking around elsewhere. I now wish I'd known to test this when my machine was running XP Media Center Edition. Reverting to this would be a big job now, I think, and I really don't have the time.

PS one thing I might try tomorrow is whether the same thing happens with lower level tone i.e. is it a function of the audio volume or the audio gain setting. So much to try, so little time....

XP on the Pavilion, playing an MP3 file through the internal speakers sounds awful, but doesn't break up when you whack the faders up full, and the performance graphs don't alter in the slightest when playing it either.

But this is what I expected. And I still can't see a reason for the behaviour reported under Vista. Can anybody else think of a possible mechanism?

With the volume right up on the Acer, 1k tone recorded at -20 has gaps, 1k tone at -40 plays without any flaws.

So it is the actual audio level, not the gain setting.

With tone at -6, the tone plays with gaps. With white noise at approx -6, the noise plays constantly.

60 seconds of white noise followed by 60 seconds of tone, plays the white noise OK, but the tone breaks up.

I thought about it, and I realised that people have complained about breakup of MP3 files played on Vista before. What they haven't noticed, and you clearly have, is that this breakup is level-dependant. And now content-dependant as well!

All of a sudden, I get very suspicious about what MS has actually done with their DR so-called M...

I'm just getting more and more baffled by this, and still haven't found enough people to test what I'm doing to get anywhere.

It now looks as though it may have something to do with vibration caused by the speakers in the 4 laptops, or maybe not. If I play my tone through the internal speakers, it plays with gaps, through headphones it doesn't. From the internal HD it plays with gaps, from a cd or from a usb stick it doesn't. When the gaps are occuring, the whole Windows interface, including Media player becomes unresponsive. If I play tones of high or low frequencies they play OK, it's just tones around 500Hz to 2 or 3K.

Play the tone from AA 1.5 and it plays cleanly, play the tone from AA 2.0 and it usually has gaps, and the whole Windows UI starts to fail. The audio level is the same in both cases.

It happens of the 4 machines, 2 from HP and 2 from Acer. I wonder if they are really the same chassis under the skin.

I just have to be missing something basic and obvious.

wildduck, do you, as an off-the-wall idea, happen to be running the "Aero" features on Vista? Try turning it OFF and see what happens.

wildduck, do you, as an off-the-wall idea, happen to be running the "Aero" features on Vista? Try turning it OFF and see what happens.

Yes, I've tried with and without and no difference. AA anyway switches off the fuzzy surrounds to the graphics that seem to be what Aero achieves!

But off the wall ideas are what I need.

But off the wall ideas are what I need.

Oh is that why you rang me up!

(actually I made a non off-the-wall suggestion that I hope he's looking in to...)

As a PS, I should also say that Wildduck played me some 1kHz tone from Vista down the phone. The gaps are, to say the very least, significant. Some of them last several seconds!

Interestingly, I just read something on the Plogue Bidule forum that may be related.  The background is the the Plogue development also contribute to open-source projects, like the portaudio library.  Also, obviously, as audio developers they have an interest in supporting Vista.  Now, it appears that they've observed some issues (surprise, surprise) with Vista's supposedly spiffy new audio engine.  Here's what David Viens says on the Bidule forum:

This pretty much gives my opinion on the subject:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1515552&SiteID=1
Still no answer from MS, its not that i didnt try.

Short version, Vista is alright (no better or worse than XP for audio), provided your manufacturer still have ASIO drivers.

With all the experimentation ive made, i think the "glitch resiliency" is really more marketing than proof. All their "glitch example is using HUGE buffers,
and as you know theres vey little chance of glitches in that situation.

If you follow the link to the Microsoft forum, you'll see a discussion about audio stuttering and the ineffectiveness of a new API that's supposed to give audio processing threads a priority boost (if I'm reading the technical details correctly).  It appears that the developers attempting to use this feature are finding that it's useless for sustained audio processing.

So, basically, it sounds like a right balls up in the implementation of the audio engine of Vista.

Why does none of the above surprise me very much? MS have a long and dishonourable history of releasing screwed software, just to see if they can get away with it. You'd have thought that by now, they would have learned that they can't.

Obviously they haven't learned anything of the sort.

The interesting point in the referenced thread though is about ASIO. To what extent does using ASIO drivers get around the problems of the scheduler? And to what extent also does this hamper/disable DRM?

I'm pretty sure that Wildduck's tests were based on standard machines using the internal audio drivers, and the other thing that he noted was that there is a significant difference in playback performance depending on the source of the file - useless from the internal HD, better/okay from a USB stick and CD. I'm not quite sure how this fits into the MMCSS scenario, but since MS's implementation of audio is convoluted, to say the least, I suppose that anything is possible...

Well now, today there are two developments.

First, someone popped up who has a HP dc5750 microtower with onboard sound and AMD 64 x2 cpus.
This played the sound fine at low and high vol.  He also has a Medion 4754 Turion 64 x2 laptop. It plays the
sound fine at low vol but exhibits the breaks in sound at high volume.

This means we now have a total of 5 laptops that show the effect versus one that doesn't.

Second, a brand new Seagate 120gig 2.5" drive arrived. I formatted NTFS and installed Vista from the Microsoft DVD, with no additional drivers or apps. It performs in the now familiar way. Low level audio mid-frequency tone through the laptop speaker plays fine, increase the level and it plays with gaps. The user interface also becomes extremely sluggish.

Next, I re-formatted the drive using the XP Pro CD as NTFS and installed XP Pro SP2. I then had to download a bunch of video and chipset drivers and also the Realtek audio driver, all from the current Acer ftp site. In this I ended up with Windows Media Player 9 and the ability to play sound.

And now drum roll or scream it does exactly the same. Gaps when the audio is turned up on tone. The UI hanging effect is in fact even worse than with Vista.

It seems that between all the laptops we have Realtek and Connexant audio chipsets all showing similar effects. Does anyone know if they are in fact the same?

I'm now retiring to think and have tea.

Neither thinking nor having tea helped much, but I have sent more thorough emails to Acer support and Realtek support.  Since sending the latter, I've established that the Dell machine that will play tone has a Realtek HD audio chip, so that probably gives them their answer.

Best of all, one of the Microsoft Vista audio development team has just posted this elsewhere

"WildDuck, we're absolutely not ignoring you, we've been actively investigating this on our end.  We're not sure what's up, and given that the problem occurs onXP as well it appears that it may be a hardware issue.

I've got a machine with the same hardware codec on it, I'm trying the file on it."

"WildDuck, we're absolutely not ignoring you, we've been actively investigating this on our end.  We're not sure what's up, and given that the problem occurs onXP as well it appears that it may be a hardware issue.

I've got a machine with the same hardware codec on it, I'm trying the file on it."

Well that's quite a novelty - actually getting a response from M$!

(Incidentally, this is post 60,000 on this site - calls for at least another cup of tea to celebrate, I think...)