Crash with PlClient

[Scarabee]

Last month, I have compiled a new PlClient with the latest published sources on Github.
There is no problem when I run one instance of the program, but when I run multiple instances on the same computer, I observ often program crashes. These crashes happen after a while and randomly.
When I run the crash.dmp with VS express 2013 I can read this:

Dump summary
--------------
File dump: crash.dmp: C: \ Users \ Michael \ AppData \ Local \ Uru Live \ Log \ crash.dmp
Last write time: 9/23/2015 4:21:03 p.m.
Process name: PlClientMB.exe: C: \ MEGA \ Games \ Plclient \ PlClientMB.exe
Process Architecture: x86
Exception code: 0xc0000005
Exception information: The thread tried to read from a virtual address or write to a virtual address for which it does not have proper access.
Information on the job: Absent

Do you have an idea about the problem ?

I don't know if it's important but I'm running on Windows 10 - Intel Core I5-460M processor 64 bits with 6GB DDR3 Memory with graphic card ATI Mobility Radeon HD 5470, 512b MB VRAM

Thanks