diff --git a/plugins/obs-ffmpeg/ffmpeg-mux/ffmpeg-mux.c b/plugins/obs-ffmpeg/ffmpeg-mux/ffmpeg-mux.c
index b4e9203bf..4610a454f 100644
--- a/plugins/obs-ffmpeg/ffmpeg-mux/ffmpeg-mux.c
+++ b/plugins/obs-ffmpeg/ffmpeg-mux/ffmpeg-mux.c
@@ -745,11 +745,11 @@ static void *ffmpeg_mux_io_thread(void *data)
 
 		// Loop to write in chunk_size chunks
 		for (;;) {
+			pthread_mutex_lock(&ffm->io.data_mutex);
+
 			shutting_down = os_atomic_load_bool(
 				&ffm->io.shutdown_requested);
 
-			pthread_mutex_lock(&ffm->io.data_mutex);
-
 			// Fetch as many writes as possible from the deque
 			// and fill up our local chunk. This may involve seeking
 			// if ffmpeg needs to, so take care of that as well.