diff --git a/demux/demux.c b/demux/demux.c
index 3032e69784..3f65b2f158 100644
--- a/demux/demux.c
+++ b/demux/demux.c
@@ -3098,18 +3098,39 @@ static void switch_current_range(struct demux_internal *in,
     free_empty_cached_ranges(in);
 }
 
+// Search for the entry with the highest index with entry.pts <= pts true.
+static struct demux_packet *search_index(struct demux_queue *queue, double pts)
+{
+    size_t a = 0;
+    size_t b = queue->num_index;
+
+    while (a < b) {
+        size_t m = a + (b - a) / 2;
+        struct index_entry *e = &QUEUE_INDEX_ENTRY(queue, m);
+
+        bool m_ok = e->pts <= pts;
+
+        if (a + 1 == b)
+            return m_ok ? e->pkt : NULL;
+
+        if (m_ok) {
+            a = m;
+        } else {
+            b = m;
+        }
+    }
+
+    return NULL;
+}
+
 static struct demux_packet *find_seek_target(struct demux_queue *queue,
                                              double pts, int flags)
 {
     pts -= queue->ds->sh->seek_preroll;
 
-    struct demux_packet *start = queue->head;
-    for (size_t n = 0; n < queue->num_index; n++) {
-        struct index_entry *e = &QUEUE_INDEX_ENTRY(queue, n);
-        if (e->pts > pts)
-            break;
-        start = e->pkt;
-    }
+    struct demux_packet *start = search_index(queue, pts);
+    if (!start)
+        start = queue->head;
 
     struct demux_packet *target = NULL;
     for (struct demux_packet *dp = start; dp; dp = dp->next) {