Canon USA has posted a PDF indicating that some people are experiencing problems with the new version 2.03 firmware. Here is the full text of the announcement:
"Thank you for using Canon products.
We have learned that some users of the Canon EOS 5D Mark II digital SLR camera are experiencing issues with Firmware Update Version 2.0.3.
We are working on a new firmware update to address these phenomena, which will be available soon.If you have not registered your EOS 5D Mark II, please register so we will be able to notify you via email when future updates become available for download.
Canon always strives to provide the highest quality products to our customers. We sincerely apologize for any inconvenience these phenomena may have caused. We appreciate your kind patronage and support." (thanks Hugh & neuroanatomist)
The Canon PDF
is available for download.
Apparently the specific problem has to do with sound recording not working when a manual record volume is used in the C modes. Update from Canon:
"Recently we have discovered a malfunction that occurs with Firmware Version 2.0.3, in which the manual recording levels for C1/C2/C3 are changed and the camera becomes unable to record audio if the power is turned off (or if Auto power off takes effect) after registering "Sound Recording: Manual" in the camera user settings.
We apologize very sincerely for the inconvenience, but we are going to stop making this firmware available for download. For customers who have already updated to the new firmware, when using the camera with the mode dial set to C1/C2/C3, please either set the sound recording settings to Auto.
We are currently preparing firmware that will correct this malfunction. As soon as those preparations have been completed, we will let you know on this Web site. In the meantime, we apologize for the inconvenience this represents, but please wait until the fixed firmware is ready."
This update is posted on the firmware download page