Q: AppleMobileDeviceService.exe is hogging up to %50 of CPU

this is happening to me too started today and then i updated to 10.4 and its still doing it. really annoying.

This is similar information.

After installing of 10.4, AppleMobileDeviceService.exe used most of CPU power. Any applications that are running on that PC became slow. I decided to downgrade of itune. It seems this is a compatibility problem between itunes 10.4 and ApplieMobileDeviceService.exe. Because  AppleMobileDeviceService.exe was same after deleting it, when I installed 10.2.2. I'd like to wait a new version which solves this compatibility problem.

Env. XP Pro(X86)

The same problem for me - after updating to the latest version of iTunes the AMDS is hogging the CPU and the ipod sync process stalls.

Anyone know how to downgrade to a previous stable version of itunes?

Same issue.  Actually, double glutton.   Upgraded and problem started.   AppleMobileDeviceService.exe is taking one processor, and iTunes takes another processor.  On a dual processor machine, that doesn't leave much.

Powered system off and did a reboot.   No apparent change.

After about 20 or 25 minutes of using a processor flat out, the iTunes usage dropped to near zero.

Also other anomalous behaviour.  Like a complaint about needing a disk in the letter position that the iPod was already connected to and for which iTunes had already finishing sync'ing.

I updated both my computers to 10.4 and got the same problem with AMDS even without my iPod plugged in. One of my PCs is running Vista 32-bit and the other is Win 7 64-bit.

Mmm, I just noticed today that this is happening - after updating to 10.4

(I can't say for certain it wasn't happening before - I was just investigating things as iTunes can no longer backup my iPad either...)

I'm pretty certain this has been an issue before where the Service was hogging even higher percentages of the CPU, even 90-100% in some cases.

Does anyone else have a sneaky suspicion that instead of fixing the problem, Apple have just tried to cap the CPU usage - perhaps based on the number of cores you have. I have 4 CPU cores, and this service hogs exactly 25% of the CPU.

Anyway, I have disabled the Service from the Windows 'Adminstrative Tools' -> 'Services' utility - and only Start it when I need to sync from iTunes - and Stop it when I'm finished.

Disabling the service worked on the PC to which I normally do not tether my iPod touch, in that it brought the CPU consumption down. However, since I seemed to need that to sync, I had to enable it, thus eliminating the effectiveness of the solution. Unfortunately, when I tried to sync my iPod with the other PC (Vista), it remained stuck on step 1 (backup?) for 5-6 hours before I decided to give up.

Reverted back to version 10.3.1 and it's all normal again. Got that version here: http://www.oldapps.com/itunes.php

How did you get 10.3.1 to recognise your iTunes library?  I tried installing it but on running it said that the library was from a newer version of iTunes so wouldn't let me use it.

I got the same error; here's what I did.

1. Locate iTunes folder, and navigate to it.

e.g. C:\Users\me\Documents\My Music\iTunes

2. Rename iTunes Library.itl to iTunes Library-10.4.itl

3. Open up the Previous iTunes Libraries folder.

4. Copy the last file in the folder - probably has the date that you upgraded to 10.4 on it. Modified date should show the date before you upgraded. Mine was dated 7-24 but had a modified date of 7-19 or 7-20.

5. Go up one directory, paste the file.

6. Rename to iTunes Library.itl

7. Open iTunes.

Thanks for that, it got iTunes 10.3.1 working again.  Unfortunately the mobile device service is still hogging the processor and it refuses to sync.

For those who are struggling with the most recent update to iTunes (10.4) not syncing your device.  Here's the link to the answer I found:

http://support.apple.com/kb/TS1567?viewlocale=en_US

I'm now back to normal. (Whatever that is!) ;-P

I have the same problem with itunes 10.4 running on Vista 32-bit using 50%+ of both CPUs..

Discovered that restarting the AMDS service corrects the problem, CPUs go to normal.  AMDS is set to automatic.

Then when iTunes is started the CPUs go back to 50%, but this seems to be normal.  When iTunes is closed, CPUs go back to normal.

If Computer is restarted, AMDS goes back up to 50%+ again.

This appears to be a problem with the way AMDS is started during computer startup.

Maybe Apple can figure that out.

I wish they had an "I have this issue too" button. Anyway, I've got the same problem on a Windows XP 32 bit machine. Gonna downgrade and hope a fix comes out soon.

I hope it works for you - even downgrading didn't work for me.