diff --git a/server/server.js b/server/server.js
index 5fd089f..1de2a08 100644
--- a/server/server.js
+++ b/server/server.js
@@ -760,6 +760,20 @@ async function assertNotLive(videoId) {
   }
 }
 
+// Format selectors for saves. `[ext=mp4]` alone is NOT enough: YouTube ships
+// AV1 in mp4 containers too, and the bot-check fallback clients (web_embedded)
+// rank the AV1 ladder as "bestvideo" — an AV1 save plays on almost nothing
+// (iOS Safari has no AV1 decoder), so cached copies errored and fell back to
+// streaming. Demand h264 (`vcodec^=avc1`) + m4a/aac first; anything exotic is
+// a last resort for videos with no avc ladder at all.
+const SAVE_MUX_FORMAT =
+  'bv*[height<=720][vcodec^=avc1]+ba[ext=m4a]/bv*[height<=720][vcodec^=avc1]+ba/'
+  + 'b[ext=mp4][vcodec^=avc1]/bv*[height<=720]+ba/b[ext=mp4]/b';
+const SAVE_DEFAULT_FORMAT =
+  'best[ext=mp4][vcodec^=avc1][acodec!=none]/'
+  + 'bv*[height<=720][vcodec^=avc1]+ba[ext=m4a]/bv*[height<=720][vcodec^=avc1]+ba/'
+  + 'best[ext=mp4][acodec!=none]/bv*[height<=720]+ba/b';
+
 // Same video + same format args requested while a download is already in
 // flight (the OPFS worker retries, then the main-thread fallback retries
 // again) share ONE yt-dlp run instead of spawning another each time.
@@ -849,7 +863,7 @@ async function ytdlpEditedDownloadResponse(videoId, fp, keep, signal) {
     await withSaveSlot(() => runYtdlpResilient([
       `https://www.youtube.com/watch?v=${videoId}`,
       '--no-warnings', '--no-playlist',
-      '-f', 'bv*[height<=720][ext=mp4]+ba[ext=m4a]/bv*[height<=720]+ba/b[ext=mp4]/b',
+      '-f', SAVE_MUX_FORMAT,
       '--merge-output-format', 'mp4',
       '--limit-rate', DOWNLOAD_RATE,
       '-o', srcTmp,
@@ -916,7 +930,7 @@ app.get('/api/download/:videoId', async (c) => {
   if (c.req.query('mux') === '1') {
     try {
       return await ytdlpDownloadResponse(videoId, fp, [
-        '-f', 'bv*[height<=720][ext=mp4]+ba[ext=m4a]/bv*[height<=720]+ba/b[ext=mp4]/b',
+        '-f', SAVE_MUX_FORMAT,
         '--merge-output-format', 'mp4',
       ], c.req.raw.signal);
     } catch (err) {
@@ -931,8 +945,7 @@ app.get('/api/download/:videoId', async (c) => {
   // "Requested format is not available".
   try {
     return await ytdlpDownloadResponse(videoId, fp, [
-      '-f', 'bestvideo[ext=mp4][acodec!=none]/bestvideo[acodec!=none]/best[ext=mp4][acodec!=none]/'
-          + 'bv*[height<=720][ext=mp4]+ba[ext=m4a]/bv*[height<=720]+ba/b',
+      '-f', SAVE_DEFAULT_FORMAT,
       '--merge-output-format', 'mp4',
     ], c.req.raw.signal);
   } catch (err) {