Canon has just released a revised version of the firmware update for the 5D Mark II to address an issue involving manual audio levels control. According to Canon,
“There was a phenomenon in which the manual recording settings made in C1/C2/C3 were changed and sound could not be recorded if manual sound recording was used in the C1/C2/C3 settings and the camera was subsequently turned off (or if Auto Power Off was activated). This does not occur in modes other than C1/C2/C3.”
Firmware version 2.0.4 is available for immediate download here and is recommended for anyone who already installed version 2.0.3.