diff --git a/libavcodec/dca_xll.c b/libavcodec/dca_xll.c
index 86e992bf1c..6eedad7eb8 100644
--- a/libavcodec/dca_xll.c
+++ b/libavcodec/dca_xll.c
@@ -1102,6 +1102,7 @@ static int copy_to_pbr(DCAXllDecoder *s, const uint8_t *data, int size, int dela
         return AVERROR(ENOMEM);
 
     memcpy(s->pbr_buffer, data, size);
+    memset(s->pbr_buffer + size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
     s->pbr_length = size;
     s->pbr_delay = delay;
     return 0;
@@ -1156,6 +1157,7 @@ static int parse_frame_pbr(DCAXllDecoder *s, const uint8_t *data, int size, DCAE
 
     memcpy(s->pbr_buffer + s->pbr_length, data, size);
     s->pbr_length += size;
+    memset(s->pbr_buffer + s->pbr_length, 0, AV_INPUT_BUFFER_PADDING_SIZE);
 
     // Respect decoding delay after synchronization error
     if (s->pbr_delay > 0 && --s->pbr_delay)