fix(subtitles): teardown mpv before re-navigation and record the real local-sub index

Destroy the mpv instance before the track-change router.replace in
replaceWithTrackSelection and goToPreviousItem, matching goToNextItem — two
overlapping decoders/surfaces during the transition OOM low-RAM devices
(CodeRabbit). addSubtitleFile now sets the live index to the downloaded local
sub's real index (LOCAL_SUBTITLE_INDEX_START - position) instead of a blanket
-100, which collided with the first local sub and mis-recorded the selection
(Copilot); it still resolves to notFound on the onTracksReady re-apply so it
doesn't clobber the freshly selected track.

app/(auth)/player/direct-player.tsx

@@ -931,6 +931,10 @@ export default function DirectPlayerPage() {
         bitrateValue: bitrateValue?.toString() ?? "",
         playbackPosition: msToTicks(progress.get()).toString(),
       }).toString();
+      // Destroy the current mpv instance before re-navigating, same rationale as
+      // goToNextItem: Expo Router briefly holds two players during the
+      // transition and two decoders/surfaces OOM-kill low-RAM devices.
+      videoRef.current?.destroy().catch(() => {});
       router.replace(`player/direct-player?${queryParams}` as any);
     },
     [
@@ -1105,6 +1109,10 @@ export default function DirectPlayerPage() {
         previousItem.UserData?.PlaybackPositionTicks?.toString() ?? "",
     }).toString();
 
+    // Free the current mpv instance before navigating, matching goToNextItem —
+    // otherwise two decoders/surfaces overlap during the transition and can
+    // OOM-kill low-RAM devices.
+    videoRef.current?.destroy().catch(() => {});
     router.replace(`player/direct-player?${queryParams}` as any);
   }, [
     previousItem,
@@ -1117,14 +1125,24 @@ export default function DirectPlayerPage() {
   ]);
 
   // TV: Add subtitle file to player (for client-side downloaded subtitles)
-  const addSubtitleFile = useCallback(async (path: string) => {
-    // Move the live index off the previous server sub BEFORE the add: the
-    // sub-add fires onTracksReady, whose re-apply would otherwise resolve the
-    // stale index and clobber the freshly selected local sub (disable it, or
-    // re-select the old track). The sentinel resolves to notFound → no-op.
-    setCurrentSubtitleIndex(LOCAL_SUBTITLE_INDEX_START);
-    await videoRef.current?.addSubtitleFile?.(path, true);
-  }, []);
+  const addSubtitleFile = useCallback(
+    async (path: string) => {
+      // Set the live index to the new local sub's REAL index BEFORE the add.
+      // Local subs are keyed LOCAL_SUBTITLE_INDEX_START - position, so use the
+      // downloaded path's position (not a blanket sentinel, which would collide
+      // with the first local sub at -100 and mis-record the selection). Any
+      // local index resolves to notFound on the onTracksReady re-apply, so it
+      // still doesn't clobber the freshly selected track; carry-over now keeps
+      // the correct local sub.
+      const locals = itemId ? getSubtitlesForItem(itemId) : [];
+      const pos = locals.findIndex((s) => s.filePath === path);
+      setCurrentSubtitleIndex(
+        LOCAL_SUBTITLE_INDEX_START - (pos >= 0 ? pos : 0),
+      );
+      await videoRef.current?.addSubtitleFile?.(path, true);
+    },
+    [itemId],
+  );
 
   // TV: Refresh subtitle tracks after server-side subtitle download
   // Re-fetches the media source to pick up newly downloaded subtitles

components/video-player/controls/TVSubtitleSheet.tsx

@@ -33,7 +33,6 @@ import {
   type SubtitleSearchResult,
   useRemoteSubtitles,
 } from "@/hooks/useRemoteSubtitles";
-import { compareTracksForMenu } from "@/utils/jellyfin/subtitleUtils";
 import { COMMON_SUBTITLE_LANGUAGES } from "@/utils/opensubtitles/api";
 
 interface TVSubtitleSheetProps {
@@ -97,19 +96,13 @@ export const TVSubtitleSheet: React.FC<TVSubtitleSheetProps> = ({
   const overlayOpacity = useRef(new Animated.Value(0)).current;
   const sheetTranslateY = useRef(new Animated.Value(300)).current;
 
-  // Order like jellyfin-web (embedded first, externals last, forced/default up).
-  const sortedTracks = useMemo(
-    () => [...subtitleTracks].sort(compareTracksForMenu),
-    [subtitleTracks],
-  );
-
   const initialSelectedTrackIndex = useMemo(() => {
     if (currentSubtitleIndex === -1) return 0;
-    const trackIdx = sortedTracks.findIndex(
+    const trackIdx = subtitleTracks.findIndex(
       (t) => t.Index === currentSubtitleIndex,
     );
     return trackIdx >= 0 ? trackIdx + 1 : 0;
-  }, [sortedTracks, currentSubtitleIndex]);
+  }, [subtitleTracks, currentSubtitleIndex]);
 
   useEffect(() => {
     if (visible) {
@@ -222,7 +215,7 @@ export const TVSubtitleSheet: React.FC<TVSubtitleSheetProps> = ({
       value: -1,
       selected: currentSubtitleIndex === -1,
     };
-    const options = sortedTracks.map((track) => ({
+    const options = subtitleTracks.map((track) => ({
       label:
         track.DisplayTitle || `${track.Language || "Unknown"} (${track.Codec})`,
       sublabel: track.Codec?.toUpperCase(),
@@ -230,7 +223,7 @@ export const TVSubtitleSheet: React.FC<TVSubtitleSheetProps> = ({
       selected: track.Index === currentSubtitleIndex,
     }));
     return [noneOption, ...options];
-  }, [sortedTracks, currentSubtitleIndex, t]);
+  }, [subtitleTracks, currentSubtitleIndex, t]);
 
   if (!visible) return null;