diff --git a/talk/media/sctp/sctpdataengine_unittest.cc b/talk/media/sctp/sctpdataengine_unittest.cc
index 37540882c..3a050ccc8 100644
--- a/talk/media/sctp/sctpdataengine_unittest.cc
+++ b/talk/media/sctp/sctpdataengine_unittest.cc
@@ -486,7 +486,13 @@ TEST_F(SctpDataMediaChannelTest, ClosesStreamsOnBothSides) {
   EXPECT_TRUE_WAIT(chan_1_sig_receiver.WasStreamClosed(4), 1000);
 }
 
-TEST_F(SctpDataMediaChannelTest, ReusesAStream) {
+// Flaky on Linux and Windows. See webrtc:4453.
+#if defined(WEBRTC_WIN) || defined(WEBRTC_LINUX)
+#define MAYBE_ReusesAStream DISABLED_ReusesAStream
+#else
+#define MAYBE_ReusesAStream ReusesAStream
+#endif
+TEST_F(SctpDataMediaChannelTest, MAYBE_ReusesAStream) {
   // Shut down channel 1, then open it up again for reuse.
   SetupConnectedChannels();
   cricket::SendDataResult result;
diff --git a/talk/media/webrtc/webrtcvideoengine_unittest.cc b/talk/media/webrtc/webrtcvideoengine_unittest.cc
index a4501b321..31eb1d867 100644
--- a/talk/media/webrtc/webrtcvideoengine_unittest.cc
+++ b/talk/media/webrtc/webrtcvideoengine_unittest.cc
@@ -2490,7 +2490,13 @@ TEST_F(WebRtcVideoMediaChannelTest, AddRemoveRecvStreams) {
   Base::AddRemoveRecvStreams();
 }
 
-TEST_F(WebRtcVideoMediaChannelTest, AddRemoveRecvStreamAndRender) {
+// Flaky on Linux only. See webrtc:4452.
+#if defined(WEBRTC_LINUX)
+#define MAYBE_AddRemoveRecvStreamAndRender DISABLED_AddRemoveRecvStreamAndRender
+#else
+#define MAYBE_AddRemoveRecvStreamAndRender AddRemoveRecvStreamAndRender
+#endif
+TEST_F(WebRtcVideoMediaChannelTest, MAYBE_AddRemoveRecvStreamAndRender) {
   Base::AddRemoveRecvStreamAndRender();
 }