Troggie, you are correct- it has nothing to do with the adapter.
Whether or not the adapter is connected, whether or not you are viewing 3D content, regardless of what the source is, even if you are directly feeding it checkerboard 3d from a compatible source without the adapter, whether or not you're wearing the glasses, the problem exists as soon as 3d mode is turned on in the TV menu.
See the attached picture. Click on the thumbnail for full-size image.
Just took this with no flash, no photoshop effects, with brightness & contrast set optimally.
With the 3d on, as shown, the entire area of the screen which should be black is in fact lit up blue quite brightly. This appears green with glasses on.
Furthermore, the test pattern at the TOP of the screen consists of TEN gray squares progressing from bright to dark. with the brightest at the left.
In 3D mode, as shown, the TV is only capable of reproducing the first THREE shades of gray. The remaining SEVEN shades of gray are completely washed out and obscured by the DLP-LINK flash/loss of black level.
So, 70 % of the dark detail and contrast is GONE in 3D mode on these sets.
Note that this image is the BEST I could get the TV to do in 3D mode. Doesn't matter whether the deepfield imager is on or off, or what I do with the brightness/contrast settings. Also note that this is shown in the "Natural" picture mode- in other words, no artificial "enhancements" that could degrade black level.
The proof is in the pudding.