diff --git a/modules/audio_mixer/frame_combiner.h b/modules/audio_mixer/frame_combiner.h
index 4c858e1..6185b29 100644
--- a/modules/audio_mixer/frame_combiner.h
+++ b/modules/audio_mixer/frame_combiner.h
@@ -23,7 +23,6 @@
 
 class FrameCombiner {
  public:
-  enum class LimiterType { kNoLimiter, kApmAgcLimiter, kApmAgc2Limiter };
   explicit FrameCombiner(bool use_limiter);
   ~FrameCombiner();
 
diff --git a/modules/audio_mixer/frame_combiner_unittest.cc b/modules/audio_mixer/frame_combiner_unittest.cc
index 36bf3a0..6c64d08 100644
--- a/modules/audio_mixer/frame_combiner_unittest.cc
+++ b/modules/audio_mixer/frame_combiner_unittest.cc
@@ -38,8 +38,6 @@
 using ::testing::IsEmpty;
 using ::testing::UnorderedElementsAreArray;
 
-using LimiterType = FrameCombiner::LimiterType;
-
 struct FrameCombinerConfig {
   bool use_limiter;
   int sample_rate_hz;