Re: PROBLEM: MacBook makes whining noise when usb-uhci active

[Gerald Britton]

On Sat, Jul 07, 2007 at 10:17:34PM -0400, Alan Stern wrote:
> > [2.] Full description of the problem/report: On my MacBook (first generation
> > Core Duo 1.83GHz), I can hear a faint whining noise that becomes audible
> > when usb-uhci is loaded and remains audible except when the USB ports are in
> > use (i.e. the noise temporarily stops when I'm copying music to my iPod).
> 
> You have a USB keyboard, right?  So the ports are always in use -- 
> unless you unplug the keyboard.
> 
> > This problem occurs on both 2.6.21  and 2.6.22-rc7, but does not occur on
> > 2.6.18.  Unloading usb-uhci when booted in 2.6.22-rc7 makes the whining
> > noise stop, but the system is useless in this state for obvious reasons.
> > The same whine does occur in OS X that occurs in 2.6.22-rc7 (though it does
> > NOT occur in 2.6.18)
> 
> Anyway it's clearly a hardware problem, even if it is triggered by 
> something in software.  About all I can suggest is to surround the 
> MacBook with something sound-absorbent.  (Not very helpful, I agree.)

I have a similar problem with my new Thinkpad X60 Tablet.  In this case,
I have a high pitched whine which is only caused when USB drivers are loaded,
I am on battery, and there are no devices connected to USB.  I suspect
something involved with CONFIG_USB_SUSPEND (which is enabled) is causing this
whine, but I haven't dug deeper to find out a more precise cause.

For reference, I'm running Fedora 7's 2.6.21-1.3228.fc7 x86_64.

				-- Gerald


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