constant Crashes

Hey guys and girls,

i am opening this topic because my nerves are done at this point.
my client always crashes when i fly into dalaran, i am in a large area(dragonblight or sholazar) or sometimes just randomly.
it always shows me that one of the following files are the reason for it

MapMem.cpp
or
M2Shared.cpp

i have googled and also tried the thing with the Large Address Aware as well as downloading the client new 2 times.

i am really out of idea´s for what i can do. maybe someone has a fix or just any sort of help

greets