Update on root cause of Digital Audio Service error


I posted a blog entry about a month ago about an issue that started appearing after customers install Update Rollup 2 for Media Center 2005.  Sometimes, while playing back live or recorded content, Media Center will stop displaying video and show a blue overlay screen with the text Digital Audio Service.  When I originally posted my previous blog entry, I had only heard from 2 people who were running into this issue, and both of them were able to resolve the issue by updating video and TV tuner drivers on their systems.  Since then, I have heard from many more people, and updating drivers has not helped in most cases (as you can see in the comments on that previous blog post).


Unfortunately, I don’t have an exact root cause or fix to pass on yet, but I have been able to learn more about what we think is happening in these scenarios.  Some of this is still speculation because we are trying to reliably reproduce this issue in our test lab and are so far basing our investigation on the diagnostics reports that some of you have been kind enough to send me so far.


There is an algorithm in the stream buffer engine (SBE) that detects dropped frames and attempts to synthesize replacement frames to minimize glitches and freezes while watching video from analog signals.  Once the dropped frame rate gets high enough, this algorithm stops being effective because there are not enough good frames to use to synthesize replacements from and we will halt video playback.  Media Center sets a threshold for dropped frames to decide when to stop trying to create replacement frames in this scenario.


The Digital Audio Service overlay message is a new message introduced in Update Rollup 2.  It is designed to catch and report low frame rates in DVB-T signals as opposed to letting the video glitch and freeze.  There is a different threshold that controls when Media Center decides to show this Digital Audio Service overlay than the threshold I previously described in the stream buffer engine for analog signals.  It appears that the threshold for this frame dropping rate is set lower than the frame rate threshold for the stream buffer engine for analog signals and therefore Media Center shows this error prematurely in some cases.


Possible causes for high dropped frame rates include the following:



  • Outdated drivers

  • Older tuner cards

  • Non Media Center processes running on the system that are CPU-intensive (because processor time otherwise used to process video frames is being spent elsewhere)

  • Weak signal strength

In cases where the Digital Audio Service overlay appears, you will see that playing back the same video in Windows Media Player will work because WMP does not have this frame replacement algorithm or varying thresholds.  However, it is likely that you will see some type of glitching around the same time in the video playback as you start seeing the overlay in Media Center.


The frame dropping thresholds that I mention above are all controlled within Media Center code, so unfortunately that means there is not a way to configure a registry setting to make the Digital Audio Service overlay appear less frequently or never.


We will be spending more time trying to isolate a repro case and determine possible fixes or workarounds for this issue and I will post additional updates as I get them.


 

Comments (35)

  1. David Ching says:

    Thanks for the update, Aaron. Much appreciated.

    It seems you’ve made good progress in figuring out that the root cause is glitches in the stream. If newer drivers produce more glitch-free performance, maybe that’s why some people report that shows recorded after updating the drivers are OK, but not the ones before.

    But since glitches can and do occur regularly (and are actually acceptable, given the PC is multitasking), is it even appropriate to assume a stream is audio-only when video frames are missing in a period of a couple seconds? Should you not show the message only when there is NO video present for a much longer time?

    At any rate, perhaps you should only show the Dgitial Audio Service message when a DVB-T (not analog) stream is being played. All my streams are analog, so I should never see this message. It’s inappropriate anyway, since I’m playing back an analog TV show, not Digital Audio!

    If you can’t do this, then I really, really encourage you to add a registry setting to disable this Digital Audio Service overlay. We got along without it before, and if there are video glitches, we’d rather see those then the overlay!

    Would it help to have one of us burn a data DVD of a malfunctioning clip and send it to you? The glitch is probably in the recording, because the message appears in the same location (within 30 seconds of starting the show from the beginning) repeatedly, no matter the load of the CPU at playback time.

    Thanks,

    David

  2. Patrick Phillips says:

    Thank you for your help. I have to same problem but i’m seeing something no one else hs posted.

    I did get the same problem with R2. I created restored my system from the restore pont right before I installed R2 and watched the recorded shows from when R2 was installed. The quality of the recording was horrible. Every two seconds the image pauses and restarts. When I watch shows recorded on the same channgel before R2 the quality is very good. So it seems that something is making the quality of the picture poor in R2. I have not any problems with quality or skippy images when watching live tv or recorded images. Even with R2 installed live tv has very good quality.

  3. Greg Gibbs says:

    While this explanation sounds good, I don’t buy it. I’ve been using MC for a year or so with analog cable and I’ve never had a problem playing back recorded shows no matter what the quality of the video. Further, the recorded shows I have that cause the Digital Audio Service message to appear were recorded from various channels and the video quality of each is good. Not only do they work in Media Player, but also in other apps (DVR Edit for example) that support DVR-MS files. There are no frames missing (at least to the naked eye). It happens in about the same amount of time no matter where the recording resumes, so I don’t buy that it’s missing frames. If it were, I could send you one of my recordings and you should be able to see this problem. And then, suddenly all my recordings are working again? I don’t think so. Keep trying.

    Greg

  4. Ted Howard says:

    Make sure that all Xbox Extenders, other Media Center Extenders, and especially the brand-spanking-new Xbox 360 get this update!

    I can’t watch my TV through my Xbox 360 because of this, and uninstalling Rollup 2 won’t help people like me because the decoding (I believe) is done on the Xbox 360.

    -Ted

  5. Jan says:

    I have a Dell Demension 8400 3.2Ghz, 1GB memory, Creative Audigy sound card, with a RADEON X850 XT Platinum Edition video card. All of the drivers are as up to date as possible. In addition I have an XBOX 360 being used as a MCE.

    All recent analog video recorded gets the blue screen "Digital Audio Service" when played back thru Media Center or the XBOX 360. The video plays fine in Windows Media Player 10. All old recorded video plays back fine in MC, XBOX, and WMP.

    Nothing has changed in the video signal quality. It is analog cable.

    If you cannot reproduce this problem in your lab I am more than happy to have you come to my house. This is not an intermittant problem or an unusual system configuration.

    At the moment your automatic update has made my media center PC useless. This machine was purchased specifically for its DVR capabilities which worked great until the update.

  6. astebner says:

    Hi Jan – I am very sorry that you are running into this issue. Can you please take a look at the blog post at http://blogs.msdn.com/astebner/archive/2005/12/02/499643.aspx and see if this suggestion helps you?

    If it does not, can you please use the steps listed at http://blogs.msdn.com/astebner/archive/2005/10/30/487031.aspx#492289 to gather a system diagnostics snapshot and send it to me via email?

    Thanks!

  7. Jan says:

    Thanks for he quick reponse. The new drivers worked. Leave it to Dell to ship a MCE certified machine without qualified drivers.

  8. Mike says:

    Aaron,

    I encountered this too and attributed it to some codes I had been playing with and also the possibility of a silent update/incompatible driver.

    I did some diagnostics and no longer get the error, but am not (according to my diag utility) running an MPEG-2 compliant codec.

    drop me a line or post when you guys discover more, would love to help beta the problem.

    mikehill33 (hotmail)

  9. Peter Parsons says:

    Has any progress been made on this since December. I encountered this problem last week for the first time. The "Digital Audio Service" screen appears on only one channel of live TV, in spite of re-scanning signals and re-assigning the guide. I am using two Black Gold digiatl cards purchased approx 3mths ago. Any help would be appreciated.

  10. Mike says:

    Hi, I experience this problem quite often while watching both live TV and recorded TV. However I’m only affected when I fast forward or rewind. It appears that there are several speeds for fast forwarding and rewinding as when I press the buttons once it works fine, but if I press it again to speed up the process I get the Digital Audio Service screen. I believe this could be evidence that Media Centre does think that it is missing frames as when I fast forward or rewind I’m effectively skipping frames (I think).

    Any further thoughts on this would be great.

  11. astebner says:

    Hi Mike – This is the first I’ve heard of this error happening only during FF/rewind actions. I will pass this information on to our TV team. What configuration do you have on your system (is it NTSC, PAL, DVB-T, etc?) Also, just to be sure, have you updated your TV tuner and video drivers?

  12. Mike says:

    Hi, I’m using PAL through a composite video cable from a satellite receiver box (sky+ UK). I found a newer Graphics driver and tested that as you suggested, but when I FF/RW the Digital Audio Screen still appears and will not go away unless I restart media centre: I have:

    Radeon X700SE graphics

    Creatix SAA7134 TV tuner

    Thanks

  13. TheRoberts says:

    I think this is starting to become a big issue here in the UK where many people are starting to use the MCE 2005. I have this problems along with many other people in the UK. Please see the forum posts at:

    http://www.thegreenbutton.com/community/shwmessage.aspx?ForumID=41&MessageID=153076&TopicPage=3

    and

    http://www.avforums.com/forums/showthread.php?t=293428&page=2

    The problem occurs in Live TV seeing the ‘Digital Audio Service’ on one of the mainstream UK channels.

    My post is:

    Here in Whitstable, Kent from the BlueBell Hill Transmitter I get the same ITV1 issue. My problem occurs with live TV. When changing to the ITV1 channel it shows the ‘Digital Audio Service’ message. It records likes this too. I was already running Rollup 2 and was receiving ITV1 no problem before.

    I have updated all drivers and put on all patches but to no avail.

    My machine is not a Dell, as has been suggested in other forums/blogs may be the issue but a custom made machine.

    Also the change seems to have coincided with the appearance of CITV on the channel list – I did not see/notice this channel before.

    However, now after updating my machine I have another problem. If I am on BBC1 then switch to watch something on Recorded TV and the switch back to live TV, I get the message ‘No TV Signal’. However, if I then change to another non BBC channel (e.g. Channel 4) and back to BBC1 it comes up fine.

    John

    M/Board: Asus P5GD2 Intel 915P

    Processor: 3Ghz P4 630 2MB S775 800FSB

    Video: GeForce PCX6600 256MB PCI-E

    RAM: 1GB PC2-4300

    Tuner: Hauppauge WinTV-HVR 1300 MCE/PCI

    HD: 160GB SATA + 200GB SATA

    My Decoder is:

    Company Name:CyberLink Corp.

    Version: 6.0.0.1402

  14. Jude says:

    I’m getting this same error, just since I upgraded to the latest Media Center rollup. Can I undo the rollup, or any other tips that might help?

    Thanks,

    Jude

  15. astebner says:

    Hi John – We have received several reports of this issue for some specific channels in the UK. We are currently investigating this issue because it appears to be different than the other cases we’ve seen up until now. I apologize for the inconvenience. I will post more about this issue when I know more.

    Hi Jude – You might want to try the workaround listed at http://blogs.msdn.com/astebner/archive/2005/12/02/499643.aspx. Hopefully this will help!

  16. Peter says:

    The problem reported on UK TV re ITV Channel appears to have been resolved, however I have no indication as to what has provided the remedy.

    Peter.

  17. TheRoberts says:

    I can concurr that the ITV1 issue has resolved here. But users still got ITV1 on their digi boxes whereas they could not in the MCE. So there must be something about they way the MCE processes the signal.

    Also my other highlighted problem ( Live TV -> Recorded TV -> Live TV … losing signal) has also been resolved by reverting back to the original Hauppauge WinTV-HVR-1300 drivers that came with the card. This appears to be a problem with the latest Hauppauge 3.1A drivers and the original 2.9 version works OK.

  18. We have found another possible root cause of Digital Audio Service overlays in Update Rollup 2 for Windows…

  19. charlie says:

    glad i found this.  i started having the same problems after installing rollup 2, the xbox 360, and the media center extender.  live tv works fine, recorded tv doesn’t give me a picture, just the "Digital Audio Service" message on a bright blue screen.

    another related problem.  i have the 360 universal remote.  before i got the 360, that remote worked fine with media center on the pc.  after getting the 360 and installing media center extender, that remote will only work media center when going through the 360.  anyone know how i can get it to work again in media center on the pc?

    overall, i’m very aggravated with rollup 2 and the media center extender.  my media center pc worked perfectly before i installed all this and now it barely works at all.  the most important thing i use it for, recording tv, is now completely broken.  

  20. astebner says:

    Hi Charlie – there are a couple of other blog posts I have made regarding the Digital Audio Service error that might apply to your system.  Can you please check them out at http://blogs.msdn.com/astebner/archive/2005/12/02/499643.aspx and http://blogs.msdn.com/astebner/archive/2006/02/06/526186.aspx and see if either of them help in your scenario?

    I’m sorry to say I’m not familiar with the remote control issue that you describe.  You may want to try to install the most recent IR rollup package from http://www.microsoft.com/downloads/details.aspx?FamilyID=b39d53f1-0ac9-433b-b488-4cab82f31dc8&DisplayLang=en and see if that helps.

  21. John says:

    I have this very problem Please keep me posted on your results . I love my brand new dell I’ve had for a year the only reason I spent so much is the fact I was able to record programs & play them back now that doesn’t work at all. I can still watch tv ok but since the roll up I get the digital audio service  error  I have chatted with dell but they want me to contact software support & pay to repair NOT FAIR I PAID QUITE A BIT FOR THE COMPUTER & ITS NOT WORKING PROPERLY BECAUSE OF SOMETHING THEY DID i BELEIVE THEY SHOULD BE RESPONSIBLE DON’T YOU?

  22. Doug M says:

    I’m sure everyone is resolving this issue now but I wanted to let you all know that once I updated the angel drivers from the link posted in the blog, the silly "Digital Audio Service Error" went away and all viewing worked perfectly again.  Coincidentally or not, I also have a xbox360 and installed the extender.  That seems to be when my problem started as well.

    Thanks for the research Aaron!

  23. astebner says:

    Hi John – I am not sure if you have seen them or not yet, but can you please take a look at the other blog posts I’ve written about the Digital Audio Service error at http://blogs.msdn.com/astebner/archive/2005/12/02/499643.aspx and http://blogs.msdn.com/astebner/archive/2006/02/06/526186.aspx and see if either of those apply to your system?

  24. Eric says:

    I have this same problem with MCE 2005. I find that when this overlay comes up, if i fast forward, then close and re-open Media Center, that it will usually play fine when i resume it. It is only if it hits the one frame that this error happens.

  25. A couple of months ago, I posted an item about Digital Audio Service errors that can be caused with Update…

  26. Craig says:

    I have a Gateway GT5040 and have a Visiontek Theatre 550 Pro Tuner card for Windows MCE. This was working fine until I installed the Media Center Extender for Xbox 360. Now I get the Digital Audio Service screen pretty much all the time when playing back recorded programs. I find that I can get rid of the blue screen by switching to "Live TV" then back to the recorded program which will then play fine for a while, but if I use the back/forward skip buttons this seems to bring back the blue screen. I haven’t tried uninstalling MCE extender to see if that will fix the problem. This is so frustrating, I am considering dumping Windows MCE and going to Linux/MythTV.

  27. astebner says:

    Hi Craig – I’m very sorry for the problems that you’ve been running into with your Media Center.  Do you see the Digital Audio Service overlay when you watch recorded content on the console, or on your Xbox 360?  This overlay can happen if there are other CPU-intensive processes running on your system.  You may want to check and see if you have other background processes or services running that might explain this.  Also, if you haven’t already, I would suggest trying to update the drivers on your system to see if that helps.

  28. Craig. says:

    It happens when watching it on the PC and via the Xbox 360. The GT5040 is pretty new and came with MCE 2005 pre-installed with rollup 2. The VisionTEK Theatre 550 Tuner card was installed after I bought the PC. It was the version specifically for MCE (with the MCE remote). My system is an Intel duo core running at 2.8 Ghz with 1GB of memory. I had this configuration running for a couple of weeks, with no problems playing back recorded programs. I am pretty sure that it was when I installed MCE extender the the problem started happening.  Monitoring the system while it was playing back recorded programs via the Xbox 360, the system was idling at 8% most of the time. No other processes were running at the time and the problem still happens… particularly when I use skip back/skip forward. The problem seems to have gotten worse, as now I cannot watch any recorded programs without the overlay popping up numerous times, which makes it pretty much unusable.

  29. astebner says:

    Hi Chris – I’m afraid I’m not sure what the cause of this issue on your system might be.  I would suggest contacting Xbox 360 technical support or your computer manufacturer for more detailed troubleshooting steps.  I’m sorry I’m not able to be more helpful here.

  30. bigfire says:

    Hi Aaron,

    I’m seeing this error come up more and more, and I’m up to date on my drivers and don’t use the two mentioned cards. So I’d really like this fixed. It seems there’s an obvious solution:

    "The frame dropping thresholds that I mention above are all controlled within Media Center code, so unfortunately that means there is not a way to configure a registry setting to make the Digital Audio Service overlay appear less frequently or never."

    Make it a registry setting and let us adjust it. That’s a nothing patch, and would at least let tecchies solve it. I’m stunned that it’s 9 months later, and you guys seem to think that having your TV picture disrupted is business as usual.

  31. This article serves as a central location for all links to troubleshooting documentation that has been

  32. Yahooadam says:

    Please for the love of god let us turn off this feature, its ridiculous

    I was running VMware the other night and sadly due to the rubbish way windows controls cores, it decided to do 1/2 of the recording on the second core, which was 100% used by vmware, so therefore, all my recordings for 1 evening wont play in Media center

    Of course they play fine in WMP, but what use is that to me

    Just give us a warning that the picture may be crap or whatever, but seriously, a slightly bugged picture is infinitely better then a screen saying "Digital Audio Service"

    9 Months and this issue hasn’t been fixed/updated/altered – typical of a MS update schedule

    Probably just an attempt to sell vista

  33. white795 says:

    I also recieved the blue screen with the "Digital Audio Servie" message on my PC when I tried playing recorded shows. Strange thing was that when I tried playing back the same recording on my TV via linksys extended, I could see the video, but did not have any sound.

    After updating the drivers, I am able to playback any new recordings on my PC, but the same new recordings will not playback with sound on my extender. Any ideas?

  34. astebner says:

    Hi White795 – I’m sorry, but I don’t have expertise in troubleshooting extender playback issues if the content plays correctly on the PC.  I’d suggest posting this question on one of the following forums to see if someone there can suggest workarounds for you to try:

    http://www.microsoft.com/windowsxp/expertzone/newsgroups/reader.mspx?dg=microsoft.public.windows.mediacenter

    http://thegreenbutton.com/forums/83/ShowForum.aspx