Linux下C++类的线程函数

最近在用C++编写一个RTSP的客户端，由于要用到线程，根据C编程的经验，写了如下代码：
class LiRtspSession
{
    public:
       void* MainThreadFunc(void* pvData);
       void* AudioProcThreadFunc(void* pvData);
       void Connect();
       //省略的代码
    private:
        pthread_t     m_hProcHandle, m_hAudioProcHandle;
        //省略的代码
};
void LiRtspSession::Connect()
{
    //create main thread creating rtsp session and receiving rtp/rtcp packet
    int ret = pthread_create(&m_hProcHandle, NULL, MainThreadFunc, this);
    if(ret != 0)
    {
         return;
    }
    //create a thread receiving audio data
    if(m_bAudioEnabled && m_eProtoType == ptUDP);
    {
         ret = pthread_create(&m_hAudioProcHandle, NULL, AudioProcThreadFunc, this);
         if(ret != 0)
         {
             return;
         }
    }
    pthread_join(m_hProcHandle, NULL);
 
    if(m_bAudioEnabled && m_eProtoType == ptUDP);
    {
          pthread_join(m_hAudioProcHandle, NULL);
    }
}
但是在编译时却出现如下错误：
    LiRtspSession.cpp: In member function ‘void LiRtspSession::Connect()’:
    LiRtspSession.cpp:176: error: argume