diff --git a/backend/app/controllers/sonolus/asset_controller.rb b/backend/app/controllers/sonolus/asset_controller.rb
index 988688a..e852816 100644
--- a/backend/app/controllers/sonolus/asset_controller.rb
+++ b/backend/app/controllers/sonolus/asset_controller.rb
@@ -166,12 +166,13 @@ def self.asset_get(type, name)
         elsif v.start_with?("!file:")
           name, srl_type = v.delete_prefix("!file:").split("/")
           srl_type ||= name
+          hash =
+            Digest::SHA1.file(
+              Rails.root.join("assets", "#{type}s", name)
+            ).hexdigest
           v = {
-            hash:
-              Digest::SHA1.file(
-                Rails.root.join("assets", "#{type}s", name)
-              ).hexdigest,
-            url: "/sonolus/assets/#{type}s/#{name}",
+            hash:,
+            url: "/sonolus/assets/#{type}s/#{name}?hash=#{hash}",
             type: srl_type
           }
         end