diff --git a/modules/system/classes/CombineAssets.php b/modules/system/classes/CombineAssets.php
index 99930cde0..95853825c 100644
--- a/modules/system/classes/CombineAssets.php
+++ b/modules/system/classes/CombineAssets.php
@@ -189,23 +189,34 @@ class CombineAssets
         $this->localPath = $cacheInfo['path'];
         $this->storagePath = storage_path('cms/combiner/assets');
 
-        $this->setHashOnCombinerFilters($cacheKey);
-
-        $combiner = $this->prepareCombiner($cacheInfo['files']);
-        $contents = $combiner->dump();
-        $mime = ($cacheInfo['extension'] == 'css') ? 'text/css' : 'application/javascript';
-
-        header_remove();
-        $response = Response::make($contents);
-        $response->header('Content-Type', $mime);
+        /*
+         * Analyse cache information
+         */
+        $lastModifiedTime = gmdate("D, d M Y H:i:s \G\M\T", array_get($cacheInfo, 'lastMod'));
+        $etag = array_get($cacheInfo, 'etag');
+        $mime = (array_get($cacheInfo, 'extension') == 'css')
+            ? 'text/css'
+            : 'application/javascript';
 
         /*
          * Set 304 Not Modified header, if necessary
          */
-        $lastModifiedTime = gmdate("D, d M Y H:i:s \G\M\T", array_get($cacheInfo, 'lastMod'));
+        header_remove();
+        $response = Response::make();
+        $response->header('Content-Type', $mime);
         $response->setLastModified(new DateTime($lastModifiedTime));
-        $response->setEtag(array_get($cacheInfo, 'etag'));
-        $response->isNotModified(App::make('request'));
+        $response->setEtag($etag);
+        $modified = !$response->isNotModified(App::make('request'));
+
+        /*
+         * Request says response is cached, no code evaluation needed
+         */
+        if ($modified) {
+            $this->setHashOnCombinerFilters($cacheKey);
+            $combiner = $this->prepareCombiner($cacheInfo['files']);
+            $contents = $combiner->dump();
+            $response->setContent($contents);
+        }
 
         return $response;
     }