diff --git a/library/core/src/main/java/com/google/android/exoplayer2/audio/TeeAudioProcessor.java b/library/core/src/main/java/com/google/android/exoplayer2/audio/TeeAudioProcessor.java
index b6a063bd14..a9afa47198 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/audio/TeeAudioProcessor.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/audio/TeeAudioProcessor.java
@@ -79,6 +79,11 @@ public final class TeeAudioProcessor extends BaseAudioProcessor {
     replaceOutputBuffer(remaining).put(inputBuffer).flip();
   }
 
+  @Override
+  protected void onFlush() {
+    flushSinkIfActive();
+  }
+
   @Override
   protected void onQueueEndOfStream() {
     flushSinkIfActive();
@@ -201,7 +206,7 @@ public final class TeeAudioProcessor extends BaseAudioProcessor {
     }
 
     private void reset() throws IOException {
-      RandomAccessFile randomAccessFile = this.randomAccessFile;
+      @Nullable RandomAccessFile randomAccessFile = this.randomAccessFile;
       if (randomAccessFile == null) {
         return;
       }
diff --git a/library/core/src/test/java/com/google/android/exoplayer2/audio/TeeAudioProcessorTest.java b/library/core/src/test/java/com/google/android/exoplayer2/audio/TeeAudioProcessorTest.java
new file mode 100644
index 0000000000..6f0a87e97b
--- /dev/null
+++ b/library/core/src/test/java/com/google/android/exoplayer2/audio/TeeAudioProcessorTest.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.audio;
+
+import static org.mockito.Mockito.verify;
+
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.audio.AudioProcessor.AudioFormat;
+import com.google.android.exoplayer2.audio.TeeAudioProcessor.AudioBufferSink;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnit;
+import org.mockito.junit.MockitoRule;
+
+/** Unit tests for {@link TeeAudioProcessorTest}. */
+@RunWith(AndroidJUnit4.class)
+public final class TeeAudioProcessorTest {
+
+  private static final AudioFormat AUDIO_FORMAT =
+      new AudioFormat(/* sampleRate= */ 44100, /* channelCount= */ 2, C.ENCODING_PCM_16BIT);
+
+  @Rule public final MockitoRule mockito = MockitoJUnit.rule();
+
+  private TeeAudioProcessor teeAudioProcessor;
+
+  @Mock private AudioBufferSink mockAudioBufferSink;
+
+  @Before
+  public void setUp() {
+    teeAudioProcessor = new TeeAudioProcessor(mockAudioBufferSink);
+  }
+
+  @Test
+  public void initialFlush_flushesSink() throws Exception {
+    teeAudioProcessor.configure(AUDIO_FORMAT);
+    teeAudioProcessor.flush();
+
+    verify(mockAudioBufferSink)
+        .flush(AUDIO_FORMAT.sampleRate, AUDIO_FORMAT.channelCount, AUDIO_FORMAT.encoding);
+  }
+}