Can't run the game on iOS8 using Unity4.6.9 and xCode7

When we try running the game we see our splash screen and then we are getting the error Thread1:EXC_BAD_ACCESS code=1 at il2cpp::icalls::mscorlib::System::String::RedirectToCreateString: It happens before any of our c# code gets executed - before Awake(). It does run properly on iOS9. Also we have managed to build and run it on Unity4.6.6 with xCode6.4 We can't find any references to this issue on the web, any help will be greatly appreciated.