1. 

   jimboden
   Moderator

   Somehow, I inadvertently posted this in Insider Announcements. My apologies.

   In another thread, I outlined a problem I was having using DPS, specifically getting drop outs when playing music in iTunes. I also indicated there was an Apple forum where users had said that iTunes was doing the same thing and that Apple had not addressed the problem. The thread in that forum went way back to 2010, but there was a post as recent as July 2011 complaining about the same thing. I tried playing music with Windows Media Player and it was drop out free when running DSP. After reading the Apple forum and trying Windows Media Player, I assumed the problem was with iTunes.

   Since then, I’ve done a few more experiments. First, I tried playing music from iTunes without DSP running, and I had no drop outs. If DSP is running, whether it’s turned on or off, I get drop outs with iTunes. Second, I tried playing music using Quick Time, which is the software iTunes uses, but started it as a standalone application. With and without DSP, I got exactly the same results as in iTunes. Third, I tried another application I have called HP Media Smart Music and got exactly the same results as with iTunes. Namely, it had drop outs with DSP running, whether it was turned on or off. When DSP was not running, it was fine. The HP Media Smart suite uses software from Cyberlink, so it’s different from iTunes, which uses Quick Time.

   Lastly, I went back to Windows Media Player and tried it again with and without DSP running and it worked flawlessly either way.

   I also tried playing a Blu Ray movie and a couple of games, Call of Duty Black Ops and Deus Ex Human Revolution and noticed no problems with DPS running.

   Obviously, I have no idea what my conclusions mean to Bongiovi, but thought I would at least share them. I don’t know what the user base is for DSP, but I seriously doubt I’m the only person having this problem.

   For the record, my system is: Intel i5 quad core processor at 2.8GH, 8GB RAM, Realtek HD on-board audio with drivers dated Aug. 2011, Windows 7 64 bit completely up-to-date.

   If I can provide any more information or try some other tests, please let me know.

   Posted 8 months ago #
2. 

   Joey Butera
   Audio and Computer Systems Engineer

   Thanks, Jim. I've done a lot of drop out related studies as part of the dev/testing team for Windows DPS. Dropouts only seem to happen to a few systems regardless of processor power. However, certain soundcards, background processes and other devices could be a culprit. We are constantly searching for ways to improve performance! On most machines DPS uses only 2% of the processor power available.

   To address the player software first, it turns out Windows Media Player and VLC are the most streamlined when it comes to processor usage. iTunes and QuickTime in the Windows environment are much more processor intensive (almost twice as much) playing the same audio/video file. On machines with slower processors this makes a big difference.

   The Digital Power Station as it appears in your Windows Sound Settings window is a virtual audio driver. That is how we capture audio from any program. Once captured the audio is sent to the DPS application itself for processing. That is why you must set your output device from within the DPS application.

   The other correlations I've made to dropouts are:
   1) Background processes like TeaTimer or other low level programs that will randomly kick in in the background.
   2) Pro Audio sound cards, being more tuned to specific recording purposes, tend to have a few issues talking to our virtual audio driver. Once again, results are random.
   3) Memory leaks. I have an old Dell Inspiron AMD X2 2.61Ghz with 4Gb RAM running Win7 x64. I see some correlation with memory leaks and dropouts on this machine. However, this could also have something to do with the M-Audio Delta Audiophile card.

   I have had almost no dropouts at on some of my older testing machines running XP. However I got a few when running Plants vs Zombies. Darn zombies!

   Also, here is the link to our Help Page with regards to dropouts: http://www.dpsplugin.com/help/doku.php?id=i_m_getting_choppy_or_glitchy_audio
   As we make new discoveries that are not random we can update this page.

   Anyhow, I really welcome any findings or specific instances of dropouts that can be replicated. It is easy for me to get this info to our Windows programmer to make tweaks as necessary. Thanks for your input!

   Posted 8 months ago #
3. 

   jimboden
   Moderator

   Hi Joey:

   Thanks a lot for the prompt reply. Yes, DPS only uses about 2% CPU on my system as well. It doesn't matter which player I'm running, CPU utilization for all of them is around 5% when I'm not doing anything else. I tried the DPC Latency Checker, as mentioned in the FAQ's, and rarely saw a latency spike. There was no correlation between latency and drop outs. Interesting observation about Windows Media Player vs. the others. I'm actually sitting here right now doing an A/B comparison by switching back and forth between iTunes and Media Player using the same song over and over again. Of course, I pause the song before switching between players. The results are consistently the same. No drop outs in Media Player but drop outs in iTunes. One thing that's interesting is that, when I run games, which tend to be resource hogs in their own right, I don't get drop outs plus the same is true with movies. The HP Media Player I mentioned in my original post, which gets really bad drop outs with music, is also used for movies using Cyberlink software, which supports Blu Ray drives.

   Oh well, I can at least enjoy the benefits of DSP in Windows Media Player. Music sounds fantastic on my Bose QC3 headphones using the Bose QC15 profile. DSP is an absolutely amazing product.

   This question is totally off topic for this thread, but I have a 2nd generation iPod Touch, which isn't supported by DSP. If I were to get a new iPod Touch, would you recommend the 4th generation model? I would imagine it has the most processing power in the current product line.

   Posted 8 months ago #
4. 

   jimboden
   Moderator

   Update.

   I played a couple of different Blu Ray movies for at least 15-20 minutes each and the audio was perfect. Next, I logged into Netflix and streamed a high def movie for about 10 minutes, with the same good result. Then I played a couple of classic movies I bought in iTunes (Independence Day and The Fifth Element). The audio was also perfect playing these movies in iTunes. This is truly strange. How can something as (theoretically) simple as music have drop out problems, but movies don't? Is the DSP processing with 256kbs music more complex than for movie sound tracks? I also measured CPU utilization and was getting between 15-20% maximum, compared to about 5% when playing music, so it certainly doesn't seem DPS is doing any less processing with movies, but perhaps it is.

   Posted 8 months ago #
5. 

   Joey Butera
   Audio and Computer Systems Engineer

   I don't think this is related to processor power. It could be a memory issue having to do with the video codec and/or the way it adjusts for video sync. I'm going talk to the guy who wrote the driver and pick his brain about this. It would be great if there was a setting or a process we just had to quit in order to fix dropouts when they pop up.

   Posted 8 months ago #

RSS feed for this topic

Reply

You must log in to post.