On Fri, Oct 1, 2010 at 12:23 PM, rosea grammostola <rosea.grammostola@xxxxxxxxx> wrote: > My thinkpad t61 makes a high frequency sound, pipipipipippi, not very > loud. Funny thing, when I stick in the usb mouse, it's gone... I only > have this issue when on battery. Suggestions for solution? Many Thinkpads (and other laptops as well) emit high-pitched noise when the CPU periodically goes into power save mode. As far as I know there is no real solution. You can change some kernel or BIOS settings to (partially) disable power saving, but that might reduce your battery life quite significantly. I once had a similar problem which could also be "solved" by plugging in USB devices. Turns out there was a bug in the USB kernel driver which caused continuous CPU wake-ups, and thus prevented the CPU from going into deep sleep modes. This stopped the noise, but also increased power consumtion by a couple of watts... Incidentally, another way to keep the CPU awake is to simply run JACK :) This page has a lot more information and many potential workarounds: http://www.thinkwiki.org/wiki/Problem_with_high_pitch_noises Dominic _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
