diff --git a/crates/bili_sync/src/downloader.rs b/crates/bili_sync/src/downloader.rs
index e17b7ee..54d0f7f 100644
--- a/crates/bili_sync/src/downloader.rs
+++ b/crates/bili_sync/src/downloader.rs
@@ -167,7 +167,8 @@ impl Downloader {
                 output_path.to_string_lossy().as_ref(),
             ])
             .output()
-            .await?;
+            .await
+            .context("failed to run ffmpeg")?;
         if !output.status.success() {
             bail!("ffmpeg error: {}", str::from_utf8(&output.stderr).unwrap_or("unknown"));
         }