diff --git a/common_audio/audio_converter.cc b/common_audio/audio_converter.cc
index c560346e99..485ec80c56 100644
--- a/common_audio/audio_converter.cc
+++ b/common_audio/audio_converter.cc
@@ -20,8 +20,6 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/numerics/safe_conversions.h"
 
-using rtc::checked_cast;
-
 namespace webrtc {
 
 class CopyConverter : public AudioConverter {
diff --git a/common_audio/sparse_fir_filter.cc b/common_audio/sparse_fir_filter.cc
index 0fc032722e..772eb82e47 100644
--- a/common_audio/sparse_fir_filter.cc
+++ b/common_audio/sparse_fir_filter.cc
@@ -45,7 +45,7 @@ void SparseFIRFilter::Filter(const float* in, size_t length, float* out) {
   }
 
   // Update current state.
-  if (state_.size() > 0u) {
+  if (!state_.empty()) {
     if (length >= state_.size()) {
       std::memcpy(&state_[0], &in[length - state_.size()],
                   state_.size() * sizeof(*in));
diff --git a/common_audio/wav_header.cc b/common_audio/wav_header.cc
index e49b7489b2..9d602e9a01 100644
--- a/common_audio/wav_header.cc
+++ b/common_audio/wav_header.cc
@@ -122,7 +122,7 @@ void FindWaveChunk(ChunkHeader* chunk_header,
     if (!readable->SeekForward(chunk_header->Size))
       return;  // EOF or error.
   }
-  return;  // EOF.
+  // EOF.
 }
 
 bool ReadFmtChunkData(FmtSubchunk* fmt_subchunk, ReadableWav* readable) {