I have posted a resolution to this issue here.
I accepted the updater’s offer to upgrade iTunes to 10.4.1.10 and the problem recurred. This time I followed the protocol from this KB article from Apple ( http://support.apple.com/kb/HT1923 ) and quelled the issue again. Next time I’ll do more experimentation with stopping and restarting the Apple Mobile Device Service (AMDS) first to see if the issue is limited to the service itself…
I ended up having to uninstall iTunes (and “Apple Mobile Device Support” and “Apple Application Support” and “Apple Software Update”) and reinstall iTunes (the rest came along for the reinstall ride) and the CPU issue went away.
I have Apple’s iTunes 10.4.0.80 for Windows installed on my Windows 7 – 64 bit machine.
I’m not exactly sure when it started but I’m pretty sure it’s with either the most recent iTunes update or the most recent Windows update (monthly patches).
My machine has variable speed fans to cool it based on CPU load so I’m sensitive to when the machine is doing something even modestly taxing. Lately the fans have been kicking up a notch regularly while I’m just reading email or some similarly low impact activity. So I see in my Process Explorer that the AppleMovileDeviceService.exe process is consistently chewing up almost exactly 12.5% of my CPU cycles all the time.
Has anybody else encountered this? Do you know of a fix?