diff --git a/library/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceFactory.java b/library/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceFactory.java
index f280cc050b..b6fa3b4e2c 100644
--- a/library/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceFactory.java
+++ b/library/src/main/java/com/google/android/exoplayer2/upstream/cache/CacheDataSourceFactory.java
@@ -68,7 +68,8 @@ public final class CacheDataSourceFactory implements DataSource.Factory {
   public CacheDataSource createDataSource() {
     return new CacheDataSource(cache, upstreamFactory.createDataSource(),
         cacheReadDataSourceFactory.createDataSource(),
-        cacheWriteDataSinkFactory.createDataSink(), flags, eventListener);
+        cacheWriteDataSinkFactory != null ? cacheWriteDataSinkFactory.createDataSink() : null,
+        flags, eventListener);
   }
 
 }