Issue with exporting a class with standard mutex member

I have a C++ class, which is exported from a dll. The class has a std::mutex member variable as given below

class WGTKERNELKERNELSERVICES_API CPSCalHelper
{
    mutex m_RampVoltageMutex;
};

I get the following compiler warning. I have tried to use the structure used for exporting template classesEXPIMP_TEMPLATE template class WGTKERNELKERNELSERVICES_API shared_ptr<vector<double>>;, which is not working with mutex. What should I do to correct this?

warning C4251: 'CPSCalHelper::m_RampVoltageMutex': class 'std::mutex' needs to have dll-interface to be used by clients of class 'CPSCalHelper'