13 Replies Latest reply: May 7, 2012 2:12 AM by buco55
buco55 Level 1 Level 1 (0 points)

Hi everyone. For the past few weeks I have been experiencing some issues with Safari. Namely when playing youtube videos on full screen (and especially on 720 or 1080 resolution) the video playback in the beginning stops while the audio playback continues. After a few seconds or a manual pause the video and audio start playing but then the video playback is jittery and every few seconds starts and stops. Additionally when listening to streaming online radio, safari stops the playback unexpectidely and every efford to restore the stream fails - even after restarting safari, safari "remembers" the last few seconds of the stream and will only play these.

 

Do you have any suggestions about what the problem might be and what can I do in order to solve it?

 

Thanks!


MacBook Pro, Mac OS X (10.7.2)
  • 1. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    Disconnect all wired peripherals.

     

    Step 1

     

    Launch the Activity Monitor application in any of the following ways:

     

    Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

     

    In the Finder, select Go Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

     

    If you’re running Mac OS X 10.7 or later, open LaunchPad. Click Utilities, then Activity Monitor in the page that opens.

     

    Select the CPU tab.

     

    Select All Processes from the menu in the toolbar, if not already selected.

     

    Click the heading of the % CPU column in the process table to sort the entries by CPU usage. You may have to click it twice to get the highest value at the top. What is it, and what is the process? Also post the values for % User, % System, and % Idle at the bottom of the window.

     

    Select the System Memory tab. What values are shown in the bottom part of the window for Page outs and Swap used?

     

    Step 2

     

    Launch the Console application in the same way as above, and select “kernel.log” from the file list. Post the dozen or so most recent messages in the log — the text, please, not a screenshot.

     

    If there are runs of repeated messages, post only one example of each. Do not post many repetitions of the same message.

  • 2. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    This is the information that I compiled based on the steps mentioned above:

     

    %CPU: The values change here rather qucikly (to be expected) and as a result the percentages might not be in the correct order, but I've made a short summary of the processes that use the most CPU

     

    Safari web matterial - between 13%-43%

    Safari - 6%

    Windowsserver - 9,4%

    kernel task - 4%

    Activity monitor - 1%-26%

    Flash Player (safari plug-in) - 1.6%

     

    %user: 21%-32%

    %system: 11%

    %idle: 51-62%

     

    Page outs: 85,7 MB

    Swap used: 39,1 MB

     

    As for the kernel.log there were lots of messages from the last few hours however these are some of the unique entries that I could spot:

     

    May  2 12:04:29 MacBook-Pro-van-Aleksandar kernel[0]: nspace-handler-set-snapshot-time: 1335953070

    May  2 12:04:34 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unable to get path for vp 0xffffff801a051078 (Downloads; ret 22; type 2)

    to get a path for vp 0xffffff8020ab32e8.  dropping the event.

    May  2 16:04:35 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unable to get path for vp 0xffffff80175470f8 (Firefox; ret 22; type 2)

    May  2 16:04:35 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unabled to get a path for vp 0xffffff80175470f8.  dropping the event.

    May  2 18:03:41: --- last message repeated 6 times ---

    May  2 18:04:27 MacBook-Pro-van-Aleksandar kernel[0]: nspace-handler-set-snapshot-time: 1335974669

    May  2 18:04:45: --- last message repeated 4 times ---

    May  2 18:04:46 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unable to get path for vp 0xffffff8020ab32e8 (mx6uvet6.default; ret 22; type 2)

    May  2 18:04:46 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unabled to get a path for vp 0xffffff8020ab32e8.  dropping the event.

    May  2 18:05:41: --- last message repeated 2 times ---

    May  2 18:24:03 MacBook-Pro-van-Aleksandar kernel[0]: EDID does not contain Extended EDID, not valid for audio

    May  2 18:28:02: --- last message repeated 1 time ---

    May  2 18:28:02 MacBook-Pro-van-Aleksandar kernel[0]: MacAuthEvent en1   Auth result for: d8:30:62:33:24:eb  MAC AUTH succeeded

    May  2 18:28:02 MacBook-Pro-van-Aleksandar kernel[0]: wlEvent: en1 en1 Link UP

    May  2 18:28:02 MacBook-Pro-van-Aleksandar kernel[0]: AirPort: RSN handshake complete on en1

    May  2 18:28:02 MacBook-Pro-van-Aleksandar kernel[0]: en1: BSSID changed to d8:30:62:33:24:eb

    May  2 18:28:10 MacBook-Pro-van-Aleksandar kernel[0]: IOSurface: buffer allocation size is zero

  • 3. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    Back up all data, then boot from your recovery partition (command-R at startup), launch Disk Utility, select your startup volume, and run Repair Disk (not Repair Permissions.) If any problems are found, repeat. Then reboot as usual.

  • 4. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    Thanks Linc for the reply. The disc seems to be OK as reported by the disk utility.

    Is there perhaps something else that can be casuing these problems?

  • 5. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    Please read this whole message before doing anything.

     

    This procedure is a diagnostic test. It’s unlikely to solve your problem. Don’t be disappointed when you find that nothing has changed after you complete it.

     

    The purpose of this exercise is to determine whether the problem is caused by third-party system modifications that load automatically at startup or login. Disconnect all wired peripherals except those needed for the test, and remove all aftermarket expansion cards. Boot in safe mode and log in to the account with the problem. The instructions provided by Apple are as follows:

     

    • Be sure your Mac is shut down.
    • Press the power button.
    • Immediately after you hear the startup tone, hold the Shift key. The Shift key should be held as soon as possible after the startup tone, but not before the tone.
    • Release the Shift key when you see the gray Apple icon and the progress indicator (looks like a spinning gear).

     

    Note: If FileVault is enabled under Mac OS X 10.7 or later, you can’t boot in safe mode.

     

    Safe mode is much slower to boot and run than normal, and some things won’t work at all, including wireless networking on certain Macs.

     

    The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

     

    Test while in safe mode. Same problem(s)?

     

    After testing, reboot as usual (i.e., not in safe mode) and verify that you still have the problem. Post the results of the test.

  • 6. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    Thanks again. While performing the diagnostic test it was not possible to play/stream any audio/vido, but after restarting the computer and the initial reindexing, the videos did play normal. After checking in the console, the following kernel.log messages are still present:

     

    May  3 00:19:15 MacBook-Pro-van-Aleksandar kernel[0]: MacAuthEvent en1   Auth result for: d8:30:62:33:24:eb  MAC AUTH succeeded

    May  3 00:19:15 MacBook-Pro-van-Aleksandar kernel[0]: wlEvent: en1 en1 Link UP

    May  3 00:19:15 MacBook-Pro-van-Aleksandar kernel[0]: AirPort: RSN handshake complete on en1

    May  3 00:19:15 MacBook-Pro-van-Aleksandar kernel[0]: en1: BSSID changed to d8:30:62:33:24:eb

    May  3 00:19:25 MacBook-Pro-van-Aleksandar kernel[0]: IOSurface: buffer allocation size is zero

    May  3 00:20:00 MacBook-Pro-van-Aleksandar kernel[0]: IOSurface: buffer allocation size is zero

    May  3 00:20:30: --- last message repeated 2 times ---

     

    I will try tomorrow with other videos and streaming audio sources and report back with an update.

  • 7. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    AfterI playing various videos and internet streams throughout the day, I did notice considerably less problems, however the issue still seems to be present. Just now, I was playing a low quality flash video and the video was all jittery and unsyncronized at times with the audio feed. Looking at the consolve, the following issues were reporrted:

     

    May  3 12:44:46 MacBook-Pro-van-Aleksandar kernel[0]: IOSurface: buffer allocation size is zero

    May  3 12:51:28: --- last message repeated 1 time ---

    May  3 12:51:28 MacBook-Pro-van-Aleksandar kernel[0]: nspace-handler-set-snapshot-time: 1336042290

    May  3 13:51:47 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unable to get path for vp 0xffffff801b4d4d10 (SDMHelpData; ret 22; type 2)

    May  3 13:51:48 MacBook-Pro-van-Aleksandar kernel[0]: add_fsevent: unabled to get a path for vp 0xffffff801b4d4d10.  dropping the event.

    May  3 15:08:00 MacBook-Pro-van-Aleksandar kernel[0]: IOSurface: buffer allocation size is zero

    May  3 18:26:23 MacBook-Pro-van-Aleksandar kernel[0]: IOAudioStream[0xffffff8014fa7400]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (1aded,674)->(1adee,2940).

    May  3 18:58:51 MacBook-Pro-van-Aleksandar kernel[0]: EDID does not contain Extended EDID, not valid for audio

    May  3 21:17:55 MacBook-Pro-van-Aleksandar kernel[0]: EDID does not contain Extended EDID, not valid for audio

     

    The most recurring message seems to be IOSurface: buffer allocation size is zero with over 40 entries throughout the day.

     

    Any further troubleshooting steps would be helpful.

     

    Thanks!

  • 8. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    Please read this whole message before doing anything.

     

    This procedure is a diagnostic test. It won’t solve your problem. Don’t be disappointed when you find that nothing has changed after you complete it.

     

    The purpose of this exercise is to determine whether the problem is localized to your user account. Enable guest logins and log in as Guest. For instructions, launch the System Preferences application, select Help from the menu bar, and enter “Set up a guest account” (without the quotes) in the search box.

     

    While logged in as Guest, you won’t have access to any of your personal files or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.

     

    Test while logged in as Guest. Same problem(s)?

     

    After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.

     

    Note: If you’ve activated “Find My Mac” or FileVault in Mac OS X 10.7 or later, then you can’t enable the Guest account. Create a new account in which to test, and delete it, including its home folder, after testing.

  • 9. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    The same problem seems to be also present in the Guest account.

  • 10. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    Please read this whole message before doing anything.

     

    This procedure is a diagnostic test. It won’t solve your problem. Don’t be disappointed when you find that nothing has changed after you complete it.

     

    Third-party system modifications are a common cause of usability problems. By a “system modification,” I mean software that affects the operation of other software — potentially for the worse. The following procedure will help identify which such modifications you've installed. Don’t be alarmed by the complexity of these instructions — they’re easy to carry out and won’t change anything on your Mac.

     

    These steps are to be taken while booted in “normal” mode, not in safe mode. If you’re now running in safe mode, reboot as usual before continuing.

     

    Below are instructions to enter some UNIX shell commands. The commands are harmless, but they must be entered exactly as given in order to work. If you have doubts about the safety of the procedure suggested here, search this site for other discussions in which it’s been followed without any report of ill effects.

     

    Some of the commands will line-wrap or scroll in your browser, but each one is really just a single line, all of which must be selected. You can accomplish this easily by triple-clicking anywhere in the line. The whole line will highlight, and you can then either copy or drag it. The headings “Step 1” and so on are not part of the commands.

     

    Note: If you have more than one user account, Step 2 must be taken as an administrator. Ordinarily that would be the user created automatically when you booted the system for the first time. The other steps should be taken as the user who has the problem, if different. Most personal Macs have only one user, and in that case this paragraph doesn’t apply.

     

    Launch the Terminal application in any of the following ways:

     

    ☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

     

    ☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

     

    ☞ If you’re running Mac OS X 10.7 or later, open LaunchPad. Click Utilities, then Terminal in the page that opens.

     

    When you launch Terminal, a text window will open with a line already in it, ending either in a dollar sign (“$”) or a percent sign (“%”). If you get the percent sign, enter “sh” (without the quotes) and press return. You should then get a new line ending in a dollar sign.

     

    Step 1

     

    Copy or drag — do not type — the line below into the Terminal window, then press return:

     

    kextstat -kl | awk '!/com\.apple/{printf "%s %s\n", $6, $7}'
    

     

    Post the lines of output (if any) that appear below what you just entered (the text, please, not a screenshot.)

     

    Step 2

     

    Repeat with this line:

     

    sudo launchctl list | sed 1d | awk '!/0x|com\.(apple|openssh|vix)|edu\.mit|org\.(amavis|apache|cups|isc|ntp|postfix|x)/{print $3}'
    

     

    This time, you'll be prompted for your login password, which won't be displayed when you type it. You may get a one-time warning not to screw up. You don't need to post the warning.

     

    Note: If you don’t have a login password, you’ll need to set one before taking this step. If that’s not possible, skip to the next step.

     

    Step 3

     

    launchctl list | sed 1d | awk '!/0x|com\.apple|edu\.mit|org\.(x|openbsd)/{print $3}'
    

     

    Step 4

     

    ls -1A /e*/mach* {,/}L*/{Ad,Compon,Ex,Fram,In,Keyb,La,Mail/Bu,P*P,Priv,Qu,Scripti,Servi,Spo,Sta}* L*/Fonts 2> /dev/null
    

     

    Important: If you synchronize with a MobileMe account, your me.com email address may appear in the output of the above command. If so, anonymize it before posting.

     

    Step 5

     

    osascript -e 'tell application "System Events" to get name of every login item' 2> /dev/null
    

     

    Remember, steps 1-5 are all drag-and-drop or copy-and-paste, whichever you prefer — no typing, except your password. Also remember to post the output.

     

    You can then quit Terminal.

  • 11. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    Step 1:

     

    No Output

     

    Step 2:

     

    com.microsoft.office.licensing.helper

     

    Step 3:

     

    com.google.keystone.user.agent

    com.google.GoogleContactSyncAgent

     

    Step 4:

     

    /Library/Components:

     

    /Library/Extensions:

     

    /Library/Frameworks:

    AEProfiling.framework

    AERegistration.framework

    AudioMixEngine.framework

    NyxAudioAnalysis.framework

    PluginManager.framework

    TSLicense.framework

    iLifeFaceRecognition.framework

    iLifeKit.framework

    iLifePageLayout.framework

    iLifeSQLAccess.framework

    iLifeSlideshow.framework

     

    /Library/Input Methods:

     

    /Library/Internet Plug-Ins:

    Flash Player.plugin

    Flip4Mac WMV Plugin.plugin

    JavaAppletPlugin.plugin

    Quartz Composer.webplugin

    QuickTime Plugin.plugin

    SharePointBrowserPlugin.plugin

    SharePointWebKitPlugin.webplugin

    Silverlight.plugin

    flashplayer.xpt

    iPhotoPhotocast.plugin

    nsIQTScriptablePlugin.xpt

     

    /Library/Keyboard Layouts:

     

    /Library/LaunchAgents:

     

    /Library/LaunchDaemons:

    com.apple.remotepairtool.plist

    com.microsoft.office.licensing.helper.plist

     

    /Library/PreferencePanes:

    Flash Player.prefPane

    Flip4Mac WMV.prefPane

     

    /Library/PrivilegedHelperTools:

    com.microsoft.office.licensing.helper

     

    /Library/QuickLook:

    GBQLGenerator.qlgenerator

    iWork.qlgenerator

     

    /Library/QuickTime:

    AppleIntermediateCodec.component

    AppleMPEG2Codec.component

    Flip4Mac WMV Advanced.component

    Flip4Mac WMV Export.component

    Flip4Mac WMV Import.component

     

    /Library/ScriptingAdditions:

     

    /Library/Spotlight:

    GBSpotlightImporter.mdimporter

    LogicPro.mdimporter

    Microsoft Office.mdimporter

    iWork.mdimporter

     

    /Library/StartupItems:

     

    /etc/mach_init.d:

     

    /etc/mach_init_per_login_session.d:

     

    /etc/mach_init_per_user.d:

     

    Library/Address Book Plug-Ins:

    SkypeABDialer.bundle

    SkypeABSMS.bundle

     

    Library/Fonts:

     

    Library/Input Methods:

    .localized

     

    Library/Internet Plug-Ins:

     

    Library/Keyboard Layouts:

     

    Library/LaunchAgents:

    com.apple.CSConfigDotMacCert-XYZ@me.com-SharedServices.Agent.plist

    com.google.GoogleContactSyncAgent.plist

    com.google.keystone.agent.plist

     

    Library/PreferencePanes:

     

    Step 5:

     

    Dropbox

  • 12. Re: Playback in safari is jittery and stops unexpectedly
    Linc Davis Level 10 Level 10 (118,140 points)

    I don't see anything there to account for your problem. To tell the truth, I doubt that you have a computer problem at all. I've been having the same issue wth YT videos on and off now for weeks, and apparently so have many others. Sometimes it helps to go back to the beginning after the video has buffered. Some have reported that they were enrolled by YT in an HTML5 beta-testing program without their knowledge, and that playback improved when they opted out of that program. Search this site for more information.

  • 13. Re: Playback in safari is jittery and stops unexpectedly
    buco55 Level 1 Level 1 (0 points)

    Thanks Linc for all the help and diagnostic tests. For the past few days I have been testing to see if/when the issue reappears and what I noticed is that it is related to flash. I've researched some other posts on these forums as well as adobe forums and apperantly the:

     

    IOSurface: buffer allocation size is zero

     

    kernel message is known to cause system hangs with Lion and Flash 10.3 or 11. The issue has also been reported to Adobe which now is actively investigating it further as indicated on this thread:

     

    http://forums.adobe.com/message/3825457

     

    Hopefully there will soon be a software fix for it.