Thank you for your responce. Now let's focus on the mute key.. If I plugged a headphone, the mute key won't mute the sound in headphone, then the mute key is lack of functional.. So that I think it's better to send a keycode, or emulate a keycode against the mute bit. ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensign option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ ibm-acpi-devel mailing list ibm-acpi-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/ibm-acpi-devel