Lukla: squares of bare rock in snowy textures

Hi. I get this in FSX and FS9 Lukla sceneries. That said, the problem is not, surely, anything to do with the Aerosoft airport installation per se, because I am flying a little way away from the airport, and if I deactivate that and the AS Lukla LC folders, the problem persists; so I am posting the question here..

You can see the issue from the screenshots (taken in FSX). These areas do not resolve into snowy textures, similar to those around them, but as you approach just become more finely focussed as they are, as rectangles of rock. As this happens all around the area, it looks quite odd and rather spoils the overall effect of flying here.

if anyone has any suggestions, that's be welcome. (Do other people see the same effect?), The last screenshot has co-ordinates (N27.49 12 E87.1 01 Alt 24200')...

Thanks,

Martin