diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 00fbbb0..8a1a5bd 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -8636,6 +8636,7 @@
 
 void AudioFlinger::RecordThread::updateOutDevices(const DeviceDescriptorBaseVector& outDevices)
 {
+    Mutex::Autolock _l(mLock);
     mOutDevices = outDevices;
     mOutDeviceTypeAddrs = deviceTypeAddrsFromDescriptors(mOutDevices);
     for (size_t i = 0; i < mEffectChains.size(); i++) {