allow caching of audio files

include/functions2.php

@@ -909,15 +909,10 @@
 
 			if ($entry->hasAttribute('src')) {
 				$src = rewrite_relative_url($rewrite_base_url, $entry->getAttribute('src'));
-
-				// check cache only for video and images for the time being
-				if ($entry->nodeName == 'img' || ($entry->parentNode && $entry->parentNode->nodeName == "video")) {
-
 				$cached_filename = CACHE_DIR . '/images/' . sha1($src);
-					$extension = $entry->tagName == 'source' ? '.mp4' : '.png';
 
 				if (file_exists($cached_filename)) {
-						$src = get_self_url_prefix() . '/public.php?op=cached_url&hash=' . sha1($src) . $extension;
+					$src = get_self_url_prefix() . '/public.php?op=cached_url&hash=' . sha1($src);
 
 					if ($entry->hasAttribute('srcset')) {
 						$entry->removeAttribute('srcset');
@@ -927,7 +922,6 @@
 						$entry->removeAttribute('sizes');
 					}
 				}
-				}
 
 				$entry->setAttribute('src', $src);
 			}