diff --git a/sub/dec_sub.c b/sub/dec_sub.c
index ec9af94abb..7e4427a40f 100644
--- a/sub/dec_sub.c
+++ b/sub/dec_sub.c
@@ -121,6 +121,10 @@ static void read_sub_data(struct dec_sub *sub, struct sub_data *subdata)
     assert(sub_accept_packets_in_advance(sub));
     char *temp = NULL;
 
+    struct sd *sd = sub_get_last_sd(sub);
+
+    sd->no_remove_duplicates = true;
+
     for (int i = 0; i < subdata->sub_num; i++) {
         subtitle *st = &subdata->subtitles[i];
         // subdata is in 10 ms ticks, pts is in seconds
@@ -161,7 +165,6 @@ static void read_sub_data(struct dec_sub *sub, struct sub_data *subdata)
         sub_decode(sub, &pkt);
     }
 
-    struct sd *sd = sub_get_last_sd(sub);
     // Hack for broken FFmpeg packet format: make sd_ass keep the subtitle
     // events on reset(), even though broken FFmpeg ASS packets were received
     // (from sd_lavc_conv.c). Normally, these events are removed on seek/reset,
@@ -169,6 +172,8 @@ static void read_sub_data(struct dec_sub *sub, struct sub_data *subdata)
     if (sd && sd->driver->fix_events)
         sd->driver->fix_events(sd);
 
+    sd->no_remove_duplicates = false;
+
     talloc_free(temp);
 }
 
diff --git a/sub/sd.h b/sub/sd.h
index 20dce8003d..fc1085f8ed 100644
--- a/sub/sd.h
+++ b/sub/sd.h
@@ -27,6 +27,10 @@ struct sd {
     struct ass_library *ass_library;
     struct ass_renderer *ass_renderer;
 
+    // If false, try to remove multiple subtitles.
+    // (Only for decoders which have accept_packets_in_advance set.)
+    bool no_remove_duplicates;
+
     // Set by sub converter
     const char *output_codec;
     char *output_extradata;
diff --git a/sub/sd_ass.c b/sub/sd_ass.c
index 21d941933c..7e863a2844 100644
--- a/sub/sd_ass.c
+++ b/sub/sd_ass.c
@@ -132,11 +132,13 @@ static void decode(struct sd *sd, struct demux_packet *packet)
         return;
     }
  not_all_whitespace:;
-    for (int i = 0; i < track->n_events; i++)
-        if (track->events[i].Start == ipts
-            && (duration <= 0 || track->events[i].Duration == iduration)
-            && strcmp(track->events[i].Text, text) == 0)
-            return;   // We've already added this subtitle
+    if (!sd->no_remove_duplicates) {
+        for (int i = 0; i < track->n_events; i++)
+            if (track->events[i].Start == ipts
+                && (duration <= 0 || track->events[i].Duration == iduration)
+                && strcmp(track->events[i].Text, text) == 0)
+                return;   // We've already added this subtitle
+    }
     if (duration <= 0) {
         iduration = 10000;
         ctx->incomplete_event = true;