I'm experiencing terrible banding in Lightroom2 on some files I had to shoot at iso 6400, in a poorly lit club. When I convert those same files in Breezebrowser Pro (which uses some sort of Canon software engine, though not the same as DPP) the banding is not evident.

The files are perhaps a half stop underexposed. I was handholding at 1/25th or so around f/2.8, trying to get a bit of focal depth. Next time I'm in this venue I'll open up to f/2 to get a better exposure. With enough light on the sensor, there's no banding to worry about in Lightroom.

I'd prefer to use Lightroom, as it's my usual workflow, but the conversions are unusable.

Is this a known issue with the 5D2 and Lightroom2? Is LR3 any better at handling slightly underexposed files from the 5D2?