Intriguing and bizaar problem with Nex 7 and LR 4.3

A friend of mine has been happily using / importing Sony Nex 7 Raw images into Lightroom 4.2 / 4.3 for a long time when suddenly this happens.

See attached image.

Note the grey border all around the image.

This file was imported with:
• No develop preset
• No metadata preset.
• Process 2012.
• Various std in the box profiles.

I have also attached a screen paste paste of the file dimensions from LR (also showing that it is a raw file and not cropped).

All Sony Nex raw files imported to a particular machine (Win 7, 64 bit) demonstrate this behavior.

So, in trying to trace the problem.

1. The crop tool was checked to make sure there was no crop applied. They grey border is not just a visual border. If you examine the jpg it is actually grey pixels consuming a large percentage of the native 6000x4000 Nex 7 resolution.

2. The Reset button was pressed also, to make sure the raw file conversion was restored to basecamp.

3. History reset.

4. A raw image imported into the same machine / software from a Nikon D300 behaves perfectly.

5. Previously imported Nex 7 Raw images are ok.

6. When the images are imported into two other machines they imports perfectly.

7. Scrapping the preference file makes no difference.

8. Overlay mode was checked, an overlay image loaded and then overlay mode turned off… just to make sure this was NO overlay.

9. Applying a crop and then removing a crop still leaves the grey border.

10. Applying the crop reduces the image dimensions to approx.. 4946 x 3293.

11. Exporting an image to jpg (as shown) leaves image with grey border. This grey border can be cropped out, but it means the resolution will reduce.

12. Exploring various scene modes / in camera crops / resolution settings on the camera does not seem to make any difference.

13. Formatting the card in the camera, take a picture, import directly from card. 3 different cards used. (No change).

14. When using the Catelog on a different machine the grey border remains.

NB Camera set to RAW + jpeg. Jpeg's import without border.

So finally last night…

……. we uninstalled Lightroom 4.3 and re-installed on a different folder. (No change).

So, we are running out of ideas.

Has anyone any suggestions.