Canon has updated the firmware for the Canon EOS 40D to version 1.0.8.  The firmware update is available for download here.

This firmware update (Version 1.0.8) incorporates the following improvements and fixes.

1. Fixes a phenomenon in which Image Stabilization operation emits a sound when certain buttons are pressed, with the EF-S 55-250mm f/4-5.6 IS lens attached to the camera.
2. Fixes a phenomenon in which the Image Stabilization operation emits a sound from the lens when IS lenses are attached to the camera.
3. Fixes a phenomenon in which a part of the image looks unnatural when reviewed on the LCD.
4. Corrects errors in the Spanish and Norwegian menu screens.

The Version 1.0.8 firmware being released this time is for cameras with firmware up to Version 1.0.5.  You can read further details and instructions on how to install the firmware on the download page.