diff --git a/src/middleware.ts b/src/middleware.ts
index 5444e4d..ec66360 100644
--- a/src/middleware.ts
+++ b/src/middleware.ts
@@ -25,19 +25,19 @@ export function cache(): Middleware {
 		const response = await cache.match(req);
 
 		if (response) {
+			// headers are immutable, so we need to clone the headers
+			// to add the Accept-Ranges header for range requests
+			const headers = new Headers(response.headers);
+			headers.set("Accept-Ranges", "bytes");
+
 			if (c.req.header("If-None-Match") === response.headers.get("ETag")) {
 				return new Response(null, {
 					status: 304,
 					statusText: "Not Modified",
-					headers: response.headers,
+					headers,
 				});
 			}
 
-			// headers are immutable, so we need to clone the headers
-			// to add the Accept-Ranges header for range requests
-			const headers = new Headers(response.headers);
-			headers.set("Accept-Ranges", "bytes");
-
 			return new Response(response.body, {
 				status: response.status,
 				statusText: response.statusText,