diff --git a/ipfs/node_test.go b/ipfs/node_test.go
index ca07dc7..8464a66 100644
--- a/ipfs/node_test.go
+++ b/ipfs/node_test.go
@@ -237,54 +237,54 @@ func TestDownload2(t *testing.T) {
 }
 
 /*
-func TestPin(t *testing.T) {
-	log := zaptest.NewLogger(t)
+	func TestPin(t *testing.T) {
+		log := zaptest.NewLogger(t)
 
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
 
-	privateKey, _, err := crypto.GenerateEd25519Key(frand.Reader)
-	if err != nil {
-		t.Fatal(err)
-	}
+		privateKey, _, err := crypto.GenerateEd25519Key(frand.Reader)
+		if err != nil {
+			t.Fatal(err)
+		}
 
-	store, err := badger.OpenDatabase(filepath.Join(t.TempDir(), "fsd.badgerdb"), log.Named("badger"))
-	if err != nil {
-		log.Fatal("failed to open badger database", zap.Error(err))
-	}
-	defer store.Close()
+		store, err := badger.OpenDatabase(filepath.Join(t.TempDir(), "fsd.badgerdb"), log.Named("badger"))
+		if err != nil {
+			log.Fatal("failed to open badger database", zap.Error(err))
+		}
+		defer store.Close()
 
-	memBlockStore := &memoryBlockStore{
-		blocks: make(map[cid.Cid][]byte),
-	}
+		memBlockStore := &memoryBlockStore{
+			blocks: make(map[cid.Cid][]byte),
+		}
 
-	node, err := ipfs.NewNode(ctx, privateKey, config.IPFS{}, memBlockStore)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer node.Close()
+		node, err := ipfs.NewNode(ctx, privateKey, config.IPFS{}, memBlockStore)
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer node.Close()
 
-	time.Sleep(time.Second)
+		time.Sleep(time.Second)
 
-	c := cid.MustParse("QmdmQXB2mzChmMeKY47C43LxUdg1NDJ5MWcKMKxDu7RgQm")
+		c := cid.MustParse("QmdmQXB2mzChmMeKY47C43LxUdg1NDJ5MWcKMKxDu7RgQm")
 
-	_, err = node.PinCID(ctx, c, func(c cid.Cid, path string) error {
-		r, err := node.DownloadCID(ctx, c, nil)
+		_, err = node.PinCID(ctx, c, func(c cid.Cid, path string) error {
+			r, err := node.DownloadCID(ctx, c, nil)
+			if err != nil {
+				return err
+			}
+			defer r.Close()
+			h := sha256.New()
+			if _, err := io.Copy(h, r); err != nil {
+				return err
+			}
+			shaChecksum := hex.EncodeToString(h.Sum(nil))
+			t.Log("pinned", c, path, shaChecksum)
+			return nil
+		})
 		if err != nil {
-			return err
-		}
-		defer r.Close()
-		h := sha256.New()
-		if _, err := io.Copy(h, r); err != nil {
-			return err
+			t.Fatal(err)
 		}
-		shaChecksum := hex.EncodeToString(h.Sum(nil))
-		t.Log("pinned", c, path, shaChecksum)
-		return nil
-	})
-	if err != nil {
-		t.Fatal(err)
+		t.Fail()
 	}
-	t.Fail()
-}
 */
diff --git a/renterd/downloader/downloader.go b/renterd/downloader/downloader.go
index 9c62932..7302a81 100644
--- a/renterd/downloader/downloader.go
+++ b/renterd/downloader/downloader.go
@@ -210,17 +210,18 @@ func (bd *BlockDownloader) doDownloadTask(task *blockResponse, log *zap.Logger)
 	}()
 
 	buf, err := bd.downloadBlockData(ctx, task.cid, task.bucket, task.key)
+	bd.mu.Lock()
 	if err != nil {
 		log.Error("failed to download block", zap.Error(err))
 		task.err = err
-		delete(bd.inflight, cidKey(task.cid))
 	} else {
 		log.Debug("block downloaded", zap.Int("size", len(buf)), zap.Duration("elapsed", time.Since(start)))
 		task.b = buf
 		bd.dataCache.Add(cidKey(task.cid), buf)
 	}
 	close(task.ch)
-
+	delete(bd.inflight, cidKey(task.cid))
+	bd.mu.Unlock()
 }
 
 func (bd *BlockDownloader) downloadWorker(ctx context.Context, n int) {
@@ -241,7 +242,7 @@ func (bd *BlockDownloader) downloadWorker(ctx context.Context, n int) {
 		task := heap.Pop(bd.queue).(*blockResponse)
 		log := log.With(zap.Stringer("cid", task.cid), zap.Stringer("priority", task.priority))
 		log.Debug("popped task from queue")
-		bd.mu.Unlock()
+		bd.mu.Unlock() // unlock prior to downloading to prevent blocking other workers
 		bd.doDownloadTask(task, log)
 	}
 }