One of the nifty elements of Sigma’s evolution to a high quality lens maker was the introduction of the “dock” that allowed them to flash new firmware to lenses – in part preventing rascally and whimsical camera manufacturers from sidelining lens models with their own firmware changes.
Not the 100-400
But the well-reviewed Sigma 100-400mm lens for EF mount had a firmware issue in the very part that allowed for firmware updates via the dock. The result: the first firmware rev (to version 0.02) requires a trip back to the factory. Sad face.
Also fixed will be an issue that affected image stabilization, where settings weren’t properly changing as users swapped between shutter and drive modes.
As is usual with Sigma, and perhaps less so with other manufacturers, the problem was first publicized by Sigma itself. The firmware updates are done free of charge.