For anybody who wants to change it:
Got to the src folder and open the files and search for this lines.
Change the 15000 to 90000 and you have a max Buffer of 9MiB instead of 1.5MiB
PrefsUnifiedDlg.cpp:
label = CFormat(wxPLURAL("File Buffer Size: %d byte", "File Buffer Size: %d bytes",
event.GetPosition() * 15000)) % (event.GetPosition() * 15000);
Preferences.h:
static uint32 GetFileBufferSize() { return s_iFileBufferSize*15000; }
static void SetFileBufferSize(uint32 val) { s_iFileBufferSize = val/15000; }
[code]
This value should be outplaced as a constant.