diff --git a/Dockerfile b/Dockerfile
index ab67ac1..d2f914b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -36,7 +36,7 @@ RUN cd /tmp/nginx-${NGINX_VERSION} \
 RUN cd /tmp/nginx-${NGINX_VERSION} && make && make install
 
 # ffmpeg dependencies.
-RUN apk add nasm yasm-dev lame-dev libogg-dev x264-dev libvpx-dev libvorbis-dev x265-dev freetype-dev libass-dev libwebp-dev rtmpdump-dev libtheora-dev opus-dev
+RUN apk add --update nasm yasm-dev lame-dev libogg-dev x264-dev libvpx-dev libvorbis-dev x265-dev freetype-dev libass-dev libwebp-dev rtmpdump-dev libtheora-dev opus-dev
 RUN echo http://dl-cdn.alpinelinux.org/alpine/edge/testing >> /etc/apk/repositories
 RUN apk add --update fdk-aac-dev