No sooner had Canon released the latest 2.0.3 firmware update for its venerable EOS 5D Mark II earlier this week than problems were discovered resulting in the company pulling the update. The long-awaited update brought a range of video shooting enhancements and audio tweaks along with fixes to the camera’s manual sensor cleaning function. However, users quickly discovered a malfunction that saw the camera unable to record audio in certain circumstances.

The 2.0.3 update added movie frame rates that allowed them to match traditional movie theater and NTSC and PAL-based TV frame rates. 1080p30 and VGA frame rates were changed to 29.97 FPS, while 1080p24 with 23.976 FPS was also added for PAL and NTSC-based systems. The ability to record at 25 FPS for 1080p and VGA was also added for PAL-based systems.

Other enhancements include a function for manually adjusting the sound recording level (64 levels) and a histogram display (brightness or RGB) for shooting movies in manual exposure. Shutter-priority AE (TV) and aperture-priority AE (AV) modes were added to the exposure modes for shooting movies and the audio sampling frequency was changed from 44.1 to 48 KHz. Finally, the update fixed a problem that saw communication between cameras with version 1.2.4 firmware and the attached lens sometimes interrupted after manual sensor cleaning.

Canon has now pulled the firmware update from its website and is warning those that have already installed it to set the sound recording settings to Auto when using the camera with the mode dial set to C1/C2/C3. This is because of the discovery of a malfunction 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 (including if Auto power off takes effect) after registering “Sound Recording: Manual” in the camera user settings.

Canon is currently working on a fix to problem and will make an update available on its website as soon as possible.