Updated to iTunes 10.5 today and now my Audio Playback IS TERRIBLE!!! HELP!!!!

I've posted in another similar thread... I have the same problem and it appears to be isolated (on my machines) to the combination of an AMD XP processor, iTunes 10.5, and MP3 files.

I take the SAME mp3 file and play it on my AMD XP 3200+ desktop and get the robomusic.

I take the SAME mp3 file and play it on my Intel Core7 laptop and it plays fine.

I take the SAME mp3 file and play it on my Pentium 4 (single core) desktop and it plays fine.

I take the SAME m4a file and it plays fine on all three PCs.

None of these problems existed prior to the iTunes 10.5 upgrade.

Looking forward to iTunes 10.5.1

In addition to the great detective work here that has narrowed down the hardware variables consistent with this sound issue, I also find it interesting that Apple now states that "iTunes 10.5 no longer requires or includes QuickTime."

While its obvious iTunes 10.5 is the issue, this removed QuickTime software dependence variable may very well also be contributing to the problem that the new iTunes 10.5 version has with its audio decoding issues on certain Windows XP hardware now.

The new version of QuickTime isn't having any audio problems on these machines.

Now that iTunes 10.5 is independent of QuickTime, it seems that it now might not be programmed to handle all the decoding scenarios on these older flavors of XP systems like it could when it relied on QuickTime in the past.

Meanwhile, I too followed the majority of what has been described here to rollback to iTunes 10.4.1 on our Windows XP machine.

If you don't both uninstall iTunes 10.5 and also the version of Bonjour it installed to be consistent, then the iTunes 10.4.1 installer will announce that it finds a newer version of Bonjour when it tries to install it's earlier version.

I did not have to uninstall QuickTime or downgrade it to a previous version. Actually, I had already updated QuickTime indepentendly to the current version a few days before iTunes 10.5 was released.

As others have stated, after you manually restore the 10.4.1 Previous iTunes Library backup file, running the iTunes 10.4.1 installer also reinstalls its version of Bonjour without announcing that it found a previous version of Bonjour or the newer version of Quicktime in my case.

aac files sound fine but mpeg files are scratchy sounding and inaudible. Is apple going to fix this?

I had iTunes 10.5 updated onto 3 machines, all 3 on XP SP3 with the following specs:

1. AMD AthlonXP 2400+
2. AMD AthlonXP 3800+
3. Acer Aspire One netbook Intel Atom N260 CPU

Yup, you guessed it BOTH AMD machines have the 'robot-like' sound output, the Aspire One output is perfect, exactly as before the update.

Looks like i'll have to go and downgrade to 10.4.x on my AMD machines until this gets sorted.... i'll tell you one thing that we can agree on - this wouldn't have happened in Steve's day (RIP Mr. Jobs) !!

Since updating to iTunes 10.5, the music playing on my AMD Athlon XP computer also sounds like it's possessed.

Moroever, I get the same robotic sound on my iphone for ringtones recently created in iTunes 10.5.

Same here. Never happened before. At least I know it's just not me. It's an itunes problem. Thing is you can't get a hold of anyone for help.

My earlier instructions are incomplete and more applications should be uninstalled to perform a downgrade (Thanks, MacMan96!).

Here are revised instructions to downgrade from iTunes 10.5 to 10.4 32 bit (Warning - all libraries and playlists must be rebuilt using this method):

1. Copy My Music/iTunes folder to a safe location
2. Control Panel - Add/Remove Programs - Uninstall iTunes
3. Control Panel - Add/Remove Programs - Uninstall Bonjour
4. Control Panel - Add/Remove Programs - Uninstall Apple Application Support (optional)
5. Control Panel - Add/Remove Programs - Uninstall QuickTime (optional - QuickTime 7.7 will be automatically reinstalled with iTunes 10.4)
6. Run CCleaner Registry Cleaner and Restart (optional/recommended - dll error during start-up will be resolved after iTunes 10.4 is reinstalled)
7. Download iTunes 10.4 from FileHippo.com (http://www.filehippo.com/download_itunes_32/10448/)
8. Run iTunes installer
9. Import music file containing mp3s (iTunes - File - Add File to library)
10. Test playback of files (should be good).
11. Restore the files you saved in Step 1 by copying the folders from back-up file to the following folders in My Music\iTunes\iTunes Media:
    1. - Automatically Add to iTunes
    2. - Books
    3. - Downloads
    4. - Mobile Applications
    5. - Music
    6. - Podcasts
12. Restart iTunes and you should be back in business. If your iPhone is iOS 5, you will need to refrain from syncing until Apple sorts this out.

The above approach is still worst-case, and I would be really really glad to hear if there was a patch for this issue. Interestingly, I also needed to unistall and downgrade Safari 5.1.1 back to 5.0.5. Safari 5.1.1 broke QuickTime and files played back with video, but no audio, even after iTunes was successfully downgraded.

Thanks again to LAOMUSIC ARTS and MacMan96 for your comments. I agree that shin_shin has identified the lack of SSE2/SSE3 on Pentium 3 and AMD processors as the issue. It is sad that iTunes’ systems requirements ("PC with a 1GHz Intel or AMD processor and 512MB of RAM") do not suggest a problem.

Message was edited by: MercuryComet. Added clarification to #5.

Yes!

Same Problem Here. Intel P3 1.4 GHz AC 97 on board sound card.

All mp3's sound like cyber-netic gobbly goop, but play fine in VLC media player.

M4A's play fine as well as Wav files.

Thanks Apple.

I'm switchin' to oranges.

Message was edited by: Radio-Master Typo (Had P4 processor now changed to read P3.)

It would be nice if Apple would just fix the problem. I myself am not willing to redo my library There has to be a plug in of some kind, Where's the guy here who said he was gonna ask a high tech friend at Apple about this issue.???????

And me too, AMD processor Windows XP professional
MP3 files fine with Real Player & Windows Media Player

Same here, Windows XP & AMD processor. All non Itunes purchased tracks affected.

I have managed to talk with 3 Apple people now (incl 1 technical) None of them have said they had heard about this problem. I have refered them to this thread (with nearly 8000 views) and the clear details in it, plus the dozern or so other threads

I have another call this evening so they can collect some Diagnostics Log files from iTunes and my phone

All very helpful and pleasant but still haven't acknowledged it's an identified problem yet and feel it's all going a bit around in cirlces.

I will keep going so Apple finally except this critical bug in iTunes 10.5.

.... bottom line iTunes doesn't play tunes any more and anyone running ios 5 just has a pretty brick or "telephone" ... not very special.

I just noticed in the import settings, under the MP3 selection, the details state optimized for MMX/SSE.

Could iTunes 10.5 be using the SSE instructions exclusively for decoding MP3's? -and not a compatible mode for processors without SSE?

Also, on one of my computers, it says using MP after optimized for MMX/SSE. What is that?