diff --git a/demos/main/proguard-rules.txt b/demos/main/proguard-rules.txt
index de5e0a4203..cd201892ab 100644
--- a/demos/main/proguard-rules.txt
+++ b/demos/main/proguard-rules.txt
@@ -1,6 +1,7 @@
 # Proguard rules specific to the main demo app.
 
 # Constructor accessed via reflection in PlayerActivity
+-dontnote com.google.android.exoplayer2.ext.ima.ImaAdsLoader
 -keepclassmembers class com.google.android.exoplayer2.ext.ima.ImaAdsLoader {
   <init>(android.content.Context, android.net.Uri);
 }
diff --git a/demos/main/src/main/proguard-rules.txt b/demos/main/src/main/proguard-rules.txt
index de5e0a4203..cd201892ab 100644
--- a/demos/main/src/main/proguard-rules.txt
+++ b/demos/main/src/main/proguard-rules.txt
@@ -1,6 +1,7 @@
 # Proguard rules specific to the main demo app.
 
 # Constructor accessed via reflection in PlayerActivity
+-dontnote com.google.android.exoplayer2.ext.ima.ImaAdsLoader
 -keepclassmembers class com.google.android.exoplayer2.ext.ima.ImaAdsLoader {
   <init>(android.content.Context, android.net.Uri);
 }
diff --git a/library/core/proguard-rules.txt b/library/core/proguard-rules.txt
index 9eefd64d62..7dc81c3f73 100644
--- a/library/core/proguard-rules.txt
+++ b/library/core/proguard-rules.txt
@@ -1,25 +1,31 @@
 # Proguard rules specific to the core module.
 
 # Constructors accessed via reflection in DefaultRenderersFactory
+-dontnote com.google.android.exoplayer2.ext.vp9.LibvpxVideoRenderer
 -keepclassmembers class com.google.android.exoplayer2.ext.vp9.LibvpxVideoRenderer {
   <init>(boolean, long, android.os.Handler, com.google.android.exoplayer2.video.VideoRendererEventListener, int);
 }
+-dontnote com.google.android.exoplayer2.ext.opus.LibopusAudioRenderer
 -keepclassmembers class com.google.android.exoplayer2.ext.opus.LibopusAudioRenderer {
   <init>(android.os.Handler, com.google.android.exoplayer2.audio.AudioRendererEventListener, com.google.android.exoplayer2.audio.AudioProcessor[]);
 }
+-dontnote com.google.android.exoplayer2.ext.flac.LibflacAudioRenderer
 -keepclassmembers class com.google.android.exoplayer2.ext.flac.LibflacAudioRenderer {
   <init>(android.os.Handler, com.google.android.exoplayer2.audio.AudioRendererEventListener, com.google.android.exoplayer2.audio.AudioProcessor[]);
 }
+-dontnote com.google.android.exoplayer2.ext.ffmpeg.FfmpegAudioRenderer
 -keepclassmembers class com.google.android.exoplayer2.ext.ffmpeg.FfmpegAudioRenderer {
   <init>(android.os.Handler, com.google.android.exoplayer2.audio.AudioRendererEventListener, com.google.android.exoplayer2.audio.AudioProcessor[]);
 }
 
 # Constructors accessed via reflection in DefaultExtractorsFactory
+-dontnote com.google.android.exoplayer2.ext.flac.FlacExtractor
 -keepclassmembers class com.google.android.exoplayer2.ext.flac.FlacExtractor {
   <init>();
 }
 
 # Constructors accessed via reflection in DefaultDataSource
+-dontnote com.google.android.exoplayer2.ext.rtmp.RtmpDataSource
 -keepclassmembers class com.google.android.exoplayer2.ext.rtmp.RtmpDataSource {
   <init>();
 }