diff --git a/src/Rtsp/Rtsp.cpp b/src/Rtsp/Rtsp.cpp
index 492eb644..73f84434 100644
--- a/src/Rtsp/Rtsp.cpp
+++ b/src/Rtsp/Rtsp.cpp
@@ -521,6 +521,10 @@ RtpHeader* RtpPacket::getHeader(){
     return (RtpHeader*)(data() + RtpPacket::kRtpTcpHeaderSize);
 }
 
+string RtpPacket::dumpString() const{
+    return ((RtpPacket *) this)->getHeader()->dumpString(size() - RtpPacket::kRtpTcpHeaderSize);
+}
+
 uint16_t RtpPacket::getSeq(){
     return ntohs(getHeader()->seq);
 }
diff --git a/src/Rtsp/Rtsp.h b/src/Rtsp/Rtsp.h
index 884176e1..20307f45 100644
--- a/src/Rtsp/Rtsp.h
+++ b/src/Rtsp/Rtsp.h
@@ -150,7 +150,11 @@ public:
         kRtpTcpHeaderSize = 4
     };
 
+    //获取rtp头
     RtpHeader* getHeader();
+    //打印调试信息
+    string dumpString() const;
+
     //主机字节序的seq
     uint16_t getSeq();
     //主机字节序的时间戳，已经转换为毫秒
diff --git a/webrtc/SrtpSession.cpp b/webrtc/SrtpSession.cpp
index cf359b7e..4591e466 100644
--- a/webrtc/SrtpSession.cpp
+++ b/webrtc/SrtpSession.cpp
@@ -244,7 +244,7 @@ namespace RTC
 		}
 
 		std::memcpy(EncryptBuffer, *data, *len);
-        EncryptBuffer[1] |= (pt & 0x7F);
+        EncryptBuffer[1] = (pt & 0x7F) | (EncryptBuffer[1] & 0x80);
 
 		srtp_err_status_t err =
 		  srtp_protect(this->session, static_cast<void*>(EncryptBuffer), reinterpret_cast<int*>(len));