diff --git a/media/engine/webrtcvoiceengine.cc b/media/engine/webrtcvoiceengine.cc
index 1ebbb0fe2b..061a16b442 100644
--- a/media/engine/webrtcvoiceengine.cc
+++ b/media/engine/webrtcvoiceengine.cc
@@ -2307,9 +2307,11 @@ void WebRtcVoiceMediaChannel::SetRawAudioSink(
 std::vector<webrtc::RtpSource> WebRtcVoiceMediaChannel::GetSources(
     uint32_t ssrc) const {
   auto it = recv_streams_.find(ssrc);
-  RTC_DCHECK(it != recv_streams_.end())
-      << "Attempting to get contributing sources for SSRC:" << ssrc
-      << " which doesn't exist.";
+  if (it == recv_streams_.end()) {
+    RTC_LOG(LS_ERROR) << "Attempting to get contributing sources for SSRC:"
+                      << ssrc << " which doesn't exist.";
+    return std::vector<webrtc::RtpSource>();
+  }
   return it->second->GetSources();
 }
 
diff --git a/media/engine/webrtcvoiceengine_unittest.cc b/media/engine/webrtcvoiceengine_unittest.cc
index 5546f1b490..4fd087ac1a 100644
--- a/media/engine/webrtcvoiceengine_unittest.cc
+++ b/media/engine/webrtcvoiceengine_unittest.cc
@@ -3300,6 +3300,18 @@ TEST_F(WebRtcVoiceEngineTestFake, PreservePlayoutWhenRecreateRecvStream) {
   EXPECT_TRUE(GetRecvStream(kSsrcX).started());
 }
 
+// Tests when GetSources is called with non-existing ssrc, it will return an
+// empty list of RtpSource without crashing.
+TEST_F(WebRtcVoiceEngineTestFake, GetSourcesWithNonExistingSsrc) {
+  // Setup an recv stream with |kSsrcX|.
+  SetupRecvStream();
+  cricket::WebRtcVoiceMediaChannel* media_channel =
+      static_cast<cricket::WebRtcVoiceMediaChannel*>(channel_);
+  // Call GetSources with |kSsrcY| which doesn't exist.
+  std::vector<webrtc::RtpSource> sources = media_channel->GetSources(kSsrcY);
+  EXPECT_EQ(0u, sources.size());
+}
+
 // Tests that the library initializes and shuts down properly.
 TEST(WebRtcVoiceEngineTest, StartupShutdown) {
   // If the VoiceEngine wants to gather available codecs early, that's fine but