diff --git a/CMakeLists.txt b/CMakeLists.txt
index e72611a2..6ea7436c 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,7 +4,7 @@ project (webrtc-streamer)
 set (WEBRTCROOT "${CMAKE_CURRENT_SOURCE_DIR}/../webrtc" CACHE STRING "WEBRTC root directory")
 set (WEBRTCDESKTOPCAPTURE "ON" CACHE STRING "WEBRTC Desktop capture")
 set (WEBRTCCHROMEBRANDED "ON" CACHE STRING "WEBRTC Chrome branded")
-set (WEBRTCVERSION "b00c469cad3f8c926fcf81ded90b90b6e1e62b9c" CACHE STRING "WEBRTC version")
+set (WEBRTCVERSION "549c9b717fcbdfdf5d76068b3dd37076a9ffeacb" CACHE STRING "WEBRTC version")
 
 if(NOT CMAKE_BUILD_TYPE)
 set (CMAKE_BUILD_TYPE "Release")
@@ -82,7 +82,7 @@ if (NOT EXISTS ${WEBRTCOBJS}/${CMAKE_STATIC_LIBRARY_PREFIX}webrtc${CMAKE_STATIC_
   endif()
 
 
-  set (WEBRTCARGS rtc_include_tests=false\nrtc_enable_protobuf=false\nrtc_build_examples=false\nrtc_build_tools=false\ntreat_warnings_as_errors=false\nenable_js_protobuf=false\nuse_glib=false\nuse_lld=false\n)
+  set (WEBRTCARGS rtc_include_tests=false\nrtc_enable_protobuf=false\nrtc_build_examples=false\nrtc_build_tools=false\ntreat_warnings_as_errors=false\nenable_js_protobuf=false\nuse_glib=false\n)
   set (WEBRTCARGS use_custom_libcxx=false\nlibyuv_use_sme=false\n${WEBRTCARGS})
   # debug/release
   if(CMAKE_BUILD_TYPE STREQUAL "Release")
@@ -115,13 +115,17 @@ if (NOT EXISTS ${WEBRTCOBJS}/${CMAKE_STATIC_LIBRARY_PREFIX}webrtc${CMAKE_STATIC_
   endif()
 
   #patch
-  file(READ ${WEBRTCROOT}/src/rtc_base/ssl_stream_adapter.h filecontent)
-  string(REPLACE "#include <vector>" "#include <vector>\n#include <optional>" filecontent "${filecontent}")
-  file(WRITE ${WEBRTCROOT}/src/rtc_base/ssl_stream_adapter.h "${filecontent}")
+#  file(READ ${WEBRTCROOT}/src/rtc_base/ssl_stream_adapter.h filecontent)
+#  string(REPLACE "#include <vector>" "#include <vector>\n#include <optional>" filecontent "${filecontent}")
+#  file(WRITE ${WEBRTCROOT}/src/rtc_base/ssl_stream_adapter.h "${filecontent}")
 
-  file(READ ${WEBRTCROOT}/src/media/base/media_channel.h filecontent)
-  string(REGEX REPLACE "ost << ToStringIfSet[^;]*;" "" filecontent "${filecontent}")
-  file(WRITE ${WEBRTCROOT}/src/media/base/media_channel.h "${filecontent}")
+  file(READ ${WEBRTCROOT}/src/third_party/perfetto/include/perfetto/tracing/track.h filecontent)
+  string(REPLACE "#include <map>" "#include <map>\n#include <optional>" filecontent "${filecontent}")
+  file(WRITE ${WEBRTCROOT}/src/third_party/perfetto/include/perfetto/tracing/track.h  "${filecontent}")
+
+#  file(READ ${WEBRTCROOT}/src/media/base/media_channel.h filecontent)
+#  string(REGEX REPLACE "ost << ToStringIfSet[^;]*;" "" filecontent "${filecontent}")
+#  file(WRITE ${WEBRTCROOT}/src/media/base/media_channel.h "${filecontent}")
   
 
   # sound support
@@ -276,6 +280,9 @@ elseif (APPLE)
     target_link_libraries (${CMAKE_PROJECT_NAME} ${CORE_FOUNDATION} ${APPLICATION_SERVICES} ${CORE_SERVICES}
                            ${CORE_AUDIO} ${AUDIO_TOOLBOX} ${IO_SURFACE} ${APP_KIT})
 else()
+    # use lld to link
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fuse-ld=lld -B${WEBRTCROOT}/src/third_party/llvm-build/Release+Asserts/bin")
+
     # libv4l2cpp
     add_definitions(-DHAVE_V4L2)
     aux_source_directory(libv4l2cpp/src LIBSRC_FILES)