diff --git a/Dockerfile b/Dockerfile
index f31802dc..003ff4b1 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -89,6 +89,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     ffmpeg \
     curl \
     gosu \
+    sox \
     && rm -rf /var/lib/apt/lists/*
 
 # Copy installed Python packages from builder stage
diff --git a/scripts/rocm-entrypoint.sh b/scripts/rocm-entrypoint.sh
index 73812e1b..47b4686a 100644
--- a/scripts/rocm-entrypoint.sh
+++ b/scripts/rocm-entrypoint.sh
@@ -18,4 +18,10 @@ done
 mkdir -p /home/voicebox/.cache/huggingface
 chown voicebox:voicebox /home/voicebox/.cache /home/voicebox/.cache/huggingface
 
+# Ensure the mounted data volume is writable by the non-root user.
+# The Dockerfile chowns /app/data at build time, but a runtime volume mount
+# re-creates it owned by root, so fix ownership here (still root) before
+# dropping privileges.
+chown -R voicebox:voicebox /app/data || true
+
 exec gosu voicebox "$@"