According to a suggestion that surfaced on Weibo (and NOT on the usual rumor site…
EOS 5D3 and EF200mm f/2L IS USM & EF800mm f/5.6L IS USM Service Note
Canon released a product advisory for the EF200mm f/2L IS USM & EF800mm f/5.6L IS USM lenses when used with an EOS 5D Mark III: It has been confirmed that when the Canon EOS 5D Mark III Digital SLR Camera is used with the EF200mm f/2L IS USM and some units of the EF800mm f/5.6L IS USM lenses […], the Lenses may emit an abnormal noise. This is not an issue of the 5D Mark III, it concerns the mentioned lenses. The units that are affected can be identified by the serial number. See the service note below to check if you have such an unit.
To Users of the Canon EOS 5D Mark III Digital SLR Camera and EF200mm f/2L IS USM and EF800mm f/5.6L IS USM Lenses
Thank you for using Canon products.
It has been confirmed that when the Canon EOS 5D Mark III Digital SLR Camera is used with the EF200mm f/2L IS USM and some units of the EF800mm f/5.6L IS USM lenses (the “Lenses”), the Lenses may emit an abnormal noise.
The Canon EOS 5D Mark III Digital SLR Camera does not need to be repaired as a result of this phenomenon.
The support measures for this phenomenon have been decided and they are as described below.
Phenomenon
If either of the Lenses is attached to the camera with the Image Stabilizer switch on the Lenses set to ON, the Image Stabilizer will synchronize with the autofocusing (AF) function and an abnormal noise may be emitted. This abnormal noise does not affect captured images.
This phenomenon only occurs when the Canon EOS 5D Mark III is used with either of the Lenses, and does not occur when such camera is used with other lenses.
Affected Products
EF200mm f/2L IS USM Lens
EF800mm f/5.6L IS USM Lens
*This phenomenon does not occur with cameras other than the EOS 5D Mark III.
*If the fifth and sixth digit of the six-digit alphanumeric number that is imprinted on the mount of the Lenses is of any of the following numbers, the Lens is affected.
EF200mm f/2L IS USM: If the fifth and sixth digit is 00, 01, or 02.
EF800mm f/5.6L IS USM:If the fifth and sixth digit is 00, 01, 02, 03, 04, 05, or 06.
How to Identify Affected Products:
Please check the six-digit alphanumeric number as indicated in the image below.
Support
The Lenses affected by this phenomenon will be inspected and repaired free of charge beginning May 21, 2012. If you own one of the affected Lenses, please contact our Customer Support Center.
This information is for residents of the United States and Puerto Rico only. If you do not reside in the USA or Puerto Rico, please contact the Canon Customer Support Center in your region.
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