diff --git a/avconv.c b/avconv.c
index 2ed590d086..9da8d8aeca 100644
--- a/avconv.c
+++ b/avconv.c
@@ -2827,7 +2827,7 @@ static void free_input_threads(void)
         InputFile *f = input_files[i];
         AVPacket pkt;
 
-        if (f->joined)
+        if (!f->fifo || f->joined)
             continue;
 
         pthread_mutex_lock(&f->fifo_lock);