diff --git a/extensions/ffmpeg/README.md b/extensions/ffmpeg/README.md
index b29c836887..fa7ac6b9fa 100644
--- a/extensions/ffmpeg/README.md
+++ b/extensions/ffmpeg/README.md
@@ -29,7 +29,8 @@ EXOPLAYER_ROOT="$(pwd)"
 FFMPEG_EXT_PATH="${EXOPLAYER_ROOT}/extensions/ffmpeg/src/main"
 ```
 
-* Download the [Android NDK][] and set its location in an environment variable:
+* Download the [Android NDK][] and set its location in an environment variable.
+  Only versions up to NDK 15c are supported currently.
 
 ```
 NDK_PATH="<path to Android NDK>"