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

[Henrique de Moraes Holschuh <hmh@hmh.eng.br>]

On Sat, 07 Jul 2007, Gerald Britton wrote:
> 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.

http://www.thinkwiki.org/wiki/Problem_with_high_pitch_noises  might give you
some hints, and yes, it is a hardware design problem.

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh
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