diff --git a/arm32v7.dockerfile b/arm32v7.dockerfile
index f60b8c7..86d9f7b 100644
--- a/arm32v7.dockerfile
+++ b/arm32v7.dockerfile
@@ -34,6 +34,7 @@ RUN \
 		mkvtoolnix \
 		sox \
 		ffmpeg && \
+	apk add mp3val --repository=https://dl-cdn.alpinelinux.org/alpine/edge/testing && \
 	echo "************ install python packages ************" && \
 	pip install --upgrade --no-cache-dir -U \
 		r128gain && \