Choppy playback for iTunes movies

Tout et une question de paramètres audio-vidéo: ordinateur+lecteur vidéo utilisé+type de fichier en cour de lecture (Fichiers différents = réglages différents autant de foi qu'il le faut). Il faut impérativement que tous ces paramètres soit compatible entre eux sinon rien d'étonnant que cela bug. Pour ce qui est du visionnage sur écran plat ,idem modifier les paramètres de sortie audio-vidéo POUR CE PERIFERIQUE. Pour résumer voir 1:format du fichier 2:réglage carte son 3:réglages carte vidéo 4:éventuellement réglages écran plat.Lent et laborieux mais qui ne cherche rien n'a rien. Bon courage,on est tous dans la même galère!

Ne pas esiter à rechercher sur le web pour plus d'infos sur tous ces paramètres.

And any issue of audio and video parameters: video player + computer + file type used in court reading (different = different settings files much faith it takes. It is imperative that all these parameters are compatible with each other if surprising that this bug. Regarding viewed on flat screen, same change output parameters AV fOR periferique. 1 to summarize see: file format 2: Setting sound card 3: 4 video card settings : possibly plat.Lent settings screen and laborious but who seeks nothing gained. Good luck, we're all in the same boat!

Esiter not to search the web for more info

I've also had this problem on my Win 7 64 bit machine, with the iTunes library on my Macmini over a wired network. I'm trying to take some iTunesU classes, and gave up on a clean and good solution; I just wanted to be able to watch the stupid thing without carting the Macmini back and forth.

I copied the mp4 file to the PC harddrive, it came up in Quicktime, and works perfectly. This certainly isn't the solution that I, or anyone else is looking for, but at least it works after a fashion.

I too amazed that Apple hasn't addressed this.

Having the same issues - movies play fine on Apple TV 3 from iTunes 11 running on a mini pc server but if I use another Windows machine and Home Sharing to try and play HD content it stutters and stalls.

If I choose to 'import' the file so it copies into the local iTunes 11 library it will then play back without issue - the same files can be played directly from a Windows network share using Quicktime or VLC - again without issue.

This only affects HD files and they all play fine on iPad / iPhone / Apple TV.

Something I have noticed is whilst monitoring network activity during playback, the Apple TV 3 pulls so much more data across the network than the PC's using iTunes do.

There is clearly something wrong with Home Sharing from iTunes > iTunes - this happens on my main PC, and both of my laptops. I’m just grateful that the Apple TV 3 playback is fine considering that’s the main reason I use iTunes.

I subscribed to Game of Thrones as my first tv show download from iTunes. I subscribed to the HD version thinking my system is well up to playing this as I have no issues with HD quality playback through VLC or Windows Media Player. I noted on playing the first episode however, that although I don't have audio sync issues, the playback is not smooth and the frame rates were poor. I had a good look through this forum's postings but I was reluctant to tweak a number of settings for one playback program when I am not experiencing issues elsewhere. I decided to tackle just iTunes and changed settings under preferences within iTunes only as well as disable wifi syncing in case that was having any effect. I was able to increase the quality of playback simply by lowering the format - firstly back to 720p which produced an acceptable result and then completely smooth frame rates on SD. Yes its annoying that I've bought HD quality only to have to drop back to SD to obtain smooth playback but it has resolved the problem without tweaking numerous other settings within my pc. Good for a temporary workaround and possibly needed for older setups. (I'm running an ageing Vista 64 bit system with 8gb RAM, Radeon 6800 series video card and intel E7400 processor)

After a lot of experiments I found that this problem leaves if you set a compatibility mode for iTunes shortcut. Compatibility with XP or Vista, both work. The only inconvenience that iTunes Store doesn't allow you to buy or rent HD video, so you have to turn compatibility mode off when buy movie and the turn it back on to watch it.

But finaly here i've found another issue - set 24 bit 48000 Hz in Windows audio settings for my playback device. It works without compatibility mode. Thanks to this forum so much!

I've got the same problem. Win 7 64. Latest drivers. intel i7 Quad core, plenty of power. But only HD 1080p videos are choppy in itunes.

If I play the same video in quicktime or windows media player, all is fine. It's just itunes and HD files.

I've followed all the advice on this thread so far. I'm lost as to what could be going on.

I've same problem on Win 7 SP1 64bit i7 3.6GHz PC. iTunes 1080p video playback is too choppy.

I guess the issue caused by not supporting hardware acceleration. It seems like a legacy app.

When I play a movie, iTunes 11.0.4 is always higher cpu usage (about 10-20 percent) than other movie player supports h.264 hardware acceleration (Windows Media Player needs only 1-2 percent or so).

How much longer do we have to wait for smooth playback?

I don't want to buy no more HD video from iTunes Store.

After experiencing this and reading a few posts here I discovered a solution for myself.

Windows 7 Professional 64 bit.

Go to sound icon lower right side, right click

choose sound playback

click on active device

click on properties

click on advanced

You will see a dropdown bar which lists various 16 and 24 bit sampling rates

Its the bits and Hz values you need to focus on.

Go to iTunes click on the upper left hand icon for drop down menu

choose preferences

choose playback

You'll notice iTunes also has both bit rates 16 and 24 as well as Hz values.

44.1 was the lowest Hz setting on iTunes

I set both my windows settings to 24 bit and 44 Hz as well as iTunes and this cleared up the problem.

There are several things going on here (if you want further understanding). Matching the values is apparently essential for iTunes media because they have very strict encoding standards. If your OS setting is at a higher bit rate/frequency than the media then it does something called oversampling. When your PC doesn't adjust correctly for oversampling the result is its pushing the digital audio signal through "too fast" Thus the words and action in the scenes are out of synch. If the pc setting is lower than the media setting then you get undersampling and the lack of effective compensation for this causes problems as well. In either situation if your pc and media aren't on the same page then your pc is doing EXTRA work to try to adapt to the media with an inaccurate sampling setting.

Interesting. I still get updates to this thread and a recent critical post landed in my inbox but yet does not appear to be here? It wasn't offensive (aside from mentioning Windows 8 and that OS itself is almost enough to turn me to the Apple dark side) so I wonder what happened to it?

Sorry to see people still having issues. Mine were resolved until I bought a new PC. Now I have to start all over again. It really shouldn't be this hard just to get a video to play correctly. My choppyness is gone but now I have s lag on the sound instead. It's like being at an old skool cinema whrn they start the audio track a fraction too early.

Hopefully this won't get removed, but I am posting from my Samsung phone so I expect that won't go down overbig.

Thanks!

Bit settings didn't match. Such an easy fix...that I probably never would have stumbled on considering it's been driving me nuts for months and I think I looked at both those properties. It's only easy in hindsight.

Thanks again

Hi all,

One fix that was mentioned earlier was changing the playback quality to 720p when that was all that was asked for. I downloaded a digital copy of Star Trek Into Darkness after getting the Blu-Ray. Yeah, it was just handy to have the digital copy on my laptop for those Star Trek emergency moments. I'd been playing it at 1080p in iTunes on my laptop, and I was getting that jerking motion (though not as bad as some of you). There would be a minute jerkiness, where a frame would skip with audio fine. In the opening titles, you could see the letters jumping backwards just momentarily. I rightclicked on the entry for ST and saw that the preferred playback should have been in 720p. So, under the Edit/Preferences Menu in Itunes, I selected the playback option and changed the Preffered Video Version to 720p and voila... No jerkiness.... and still decent HD. So maybe this is simply a version issue. I don't download movies or tv from iTunes at all, and simply try and buy Blu-Rays with digital codes, but I'n surprised the standard isn't 1080p

Hope this helps at least some of you....always check the preffered playback version...

I'm still getting choppy playback on all of my purchased and digital copy films after trying the settings recommended here. Is there any software that could help with the problem? Could using windows 8 operating system create any problems?

thanks for this information. I just put a system together and it is not lacking in resources. Everything was working perfectly until I tried to watch one of my many itunes purchased movies. (.m4v).

I tried everything then I saw your note on matching the audio settings in itunes preferences and playback devices. It worked perfectly. It is amazing how something like this can cause so many headaches.

I'm using Win 8.1

thanks again.....

So I to have been having this problem for ages and see no sign of Apple fixing. But I think I may have found the issue and am keen for others to test. First to clarify - 720 plays fine, but 1080 has random stuttering. Its not the wifi syncing or any of the other causes listed (I have tried them all). I have a high end PC. i7 920 and GTX780 but noticed that the clock speed was stepping down (Intel EIST) when it was playing. So I went into the BIOS and turned of EIST, C1E etc and made sure the CPU stayed at clock speed and was prevented from going into energy saving mode.

And suddenly the stuttering was gone. I watched a movie last night purchased on itunes and it played almost perfectly. (I think I saw a couple of frames drop here and there) but no horrible stuttering.

I am keen to see if others can try this to see if it is the actual cause. In the mean time I'll keep wathcing a few more 1080's to see if it is really fixed.