Apple TV 3 + AirPort Extreme 5G + 2012 MBA = Laggy AirPlay mirroring

Discussion in 'Apple TV and Home Theater' started by Narial Taster, Oct 25, 2012.

  1. macrumors member

    May 17, 2011
    I have a 2012 MacBook Air, Apple TV (3rd generation), and AirPort Extreme (5th generation) and hooked them up to my HDTV to watch videos using AirPlay Mirroring. Standard Definition videos and iTunes HD content run perfectly well but 720p HD mkv files stutter/lag. The choppiness isn't so bad as to make them unwatchable but the videos don't run fluidly and once you notice it you can't ignore it! The problem is most apparent during long pans shots and fast action sequences.

    My laptop connects to the router at 300 Mbit/s and I wired the Apple TV to the router as that seems to be the commonly prescribed fix. However, this didn't help at all. Before I wired my Apple TV to the router it was connecting at 65 Mbit/s, which surprisingly seems to be the fastest speed at which the two can connect.

    I am very disappointed, especially as I have the latest hardware and don't see why AirPlay Mirroring isn't working as it's supposed to. I bought the Apple TV and the AirPort Extreme pretty much solely for mirroring stuff off my Mac. Any help would be much appreciated!
  2. fridgeymonster3, Oct 25, 2012
    Last edited: Oct 25, 2012

    macrumors 6502

    Jan 28, 2008
    It could just be the conversion from 24 fps to 30 fps. HD content shot natively at 24 fps can have a noticeable stutter on pan shots when converted to 30 fps. There isn't a solution to the problem because the Apple TV 3 doesn't support 24 fps, just 30 fps.
  3. macrumors 601


    Jan 6, 2005
    I would try an app like Beamer designed exclusively for this purpose. AirPlay mirroring just isn't well suited to smooth video streaming.
  4. macrumors member

    Oct 27, 2010
    did you try all wired....macbook to router and apple tv to router both...try this so that to rule out wifi interference.
  5. J@ffa, Oct 27, 2012
    Last edited: Oct 27, 2012

    macrumors 6502a


    Jul 21, 2002
    Behind you!
    You're not really meant to stream movies via the AirPlay mirroring function, but rather through iTunes itself. Remuxing your content from MKV to M4V files would be the best way to accomplish this. This is a fairly simplistic analogy, but what you're currently doing is roughly equivalent to watching a movie and trying to describe it in real time to someone sitting next you. However good you are at describing it to the other person, there's always going to be a delay. Obviously with a computer the delay is lessened, but it's an unnecessary extra link in the chain.
  6. thread starter macrumors member

    May 17, 2011
    Thanks a ton for that recommendation! Beamer is exactly what I was looking for and works beautifully so far. I can now use my Apple TV the way that I originally intended to.

    I've wired the Apple TV to the router as they happen to be next to each other anyway but connecting the computer to the router kind of defeats the purpose of getting an Apple TV as it is meant to enable you to cut the cord and go mobile without worrying about running cables all over the house. Also, I have a MacBook Air and so wiring it to the router would create a hassle of its own!
  7. macrumors 603

    Jun 7, 2011
    Surely not. It's because of MKV that he's experiencing stuttering. Which is understandable, as the ATV can only stream natively supported video files as is - that is, mp4 / m4v / mov files only. MKV's need to be played back using brute force - hence the stuttering.

    There isn't any other solution to the problem than remuxing to a mp4 / m4v / mov file.


    It is if (and only if) you play back natively supported files (see list above). Then, ATV will pre-cache the file itself and won't play back streamed content.
  8. macrumors 68020


    Apr 15, 2004
    Washington DC
    I would remux the MKV's as M4V's. You can do it without touching the video.
  9. macrumors 601


    Jan 6, 2005
    Are you sure that natively supported files are decoded by the ATV when displayed via AirPlay mirroring from a Mac? It would have to negotiate one stream for the video file, and another stream for the rest of the content displayed on the screen, and somehow keep them in sync. Doesn't sound likely.

    Anyhow, using Airplay mirroring to play supported file types on the ATV is pointless - you'd just use home sharing which works flawlessly and doesn't tie up the host computer while doing it. The whole point for people looking at using this as a solution is to get content that they can't otherwise get on their TV's - primarily web content, I'd wager.
  10. macrumors 603

    Jun 7, 2011
    At least when your media player on the Mac is running in full screen, I think it does. (I haven't tested this myself. It's working the way I've outlined with iOS clients - that is, native streams are decoded by the ATV itself, while non-native ones are transferred via standard - and far inferior - screen mirroring.)
  11. macrumors newbie


    Mar 5, 2010
    Zurich - Switzerland
    Similar Problem

    I have a similar problem.

    I noticed a strage behavior with my apple tv.
    I took a home video exported from Final Cut Pro X for AppleTV format (1080p).

    When I AirPlay mirror the movie it via iTunes, my network upload speed is about 30-40 Mbit/s and the movie plays very fluid. (see pic)

    When I AirPlay mirror the same movie but now directly from the computer, my network upload speed is only 9-12 Mbit/s and the movie shutters. (see pic)

    On both cases I had 300 Mbit/s transmit speed.

    This only happened when I upgraded to 10.8.2. Before my upload speed with Airplay Mirror from the computer was also 30-40 Mbit/s and it played great. I have a feeling that 10.8.2 is buggy and slows down AirPlay Mirroring.

    Any thoughts?

    Attached Files:

  12. macrumors 6502

    Jul 8, 2012
    It seems many people in this thread don't understand the difference between playing a video via Airplay, and Airplay Mirroring.

    If you play a video from iTunes and click the little Airplay icon and stream the video to your Apple TV, you are streaming via Airplay. This method streams the selected video file across your network to your Apple TV.

    If you click the Airplay icon in your menu bar and turn on Airplay Mirroring, you are doing something else entirely. This method (Mirroring) is meant for sharing your desktop to Apple TV, for things like presentations, etc.

    Playing video via Airplay (not mirroring) is sends only the video file over the network to the TV. Whereas mirroring is effectively recording and streaming video of your desktop, and does not do so at anywhere near a high enough framerate to enjoy a movie!
  13. macrumors newbie


    Mar 5, 2010
    Zurich - Switzerland
    We understand the difference very well.
    That is not the issue discussed here.

    With 10.8.2, Airplay Mirroring upload speed has slowed down!

    Before 10.8.2 I had no problem getting 25-40 Mbit/s, after 10.8.2, the maximum upload speed I get is 12 Mbit/s. When I downgraded my MBA to 10.8.1 upload speeds doubled and 1080p movies played fluidly again.
  14. macrumors newbie


    Mar 5, 2010
    Zurich - Switzerland

    Running the 10.8.3 beta and noticed that my laggy Airplay is gone !
  15. Guest


    Jun 3, 2002
    Are you by any chance connecting via 5Ghz ? my Macbook Pro has a bug where it will connect at full 300mbps, then very quickly drop to 9mbps, press alt (i think) and click on the Airport menubar icon, it tells you the transmit rate.

    I have to connect via 2.4ghz to get anywhere near a decent speed.
  16. macrumors G4


    Jun 12, 2012
    so glad you posted this. The lag always drove me crazy when trying to watch movies not in itunes using mirroring.
  17. macrumors newbie


    Mar 5, 2010
    Zurich - Switzerland

    Yes, connection on 5Ghz works much better.
    I noticed that the upload thru-put was more consistent watching 1080p movies.
  18. macrumors newbie

    Dec 17, 2012
    What about the bit rates?

    Can you measure how fast it is transmitting in 10.8.3 please?
    They said that 10.8.3 would have enhanced graphic drivers and focus on airplay , so maybe it is a fix for once?
    I have the same annoying stutter, and as much as we can remix, re-encode and use 3rd party programs, it is really annoying when playing web-videos as well...

    I never tried mirroring a videoplayback before 10.8.2, so i have never seen this work properly...

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