diff --git a/Makefile b/Makefile
index aced81b..6f9ad62 100644
--- a/Makefile
+++ b/Makefile
@@ -14,8 +14,9 @@ TOOLSDIR = tools
 FONTSDIR = fonts
 OBJDIR = ${BUILDDIR}/obj
 
-CFLAGS = -g -O2 -flto -std=gnu18 -Wall -DVERSION=\"${VERSION}\"
-LDFLAGS = -g -O2 -flto -std=gnu18 -Wall
+# TODO: Why does -flto fail on GCC 11?
+CFLAGS = -g -O3 -std=gnu18 -Wall -DVERSION=\"${VERSION}\"
+LDFLAGS = -g -O3 -std=gnu18 -Wall
 
 ifeq (${PLATFORM},mingw32-sdl)
 USE_SDL = 1
diff --git a/src/audio_stream.c b/src/audio_stream.c
index ab69c45..502ec95 100644
--- a/src/audio_stream.c
+++ b/src/audio_stream.c
@@ -121,7 +121,7 @@ void audio_stream_generate(long time, u8 *stream, int len) {
 	int i; long j;
 	int freq_samples_fixed;
 	int pos_samples_fixed;
-	int k, note_played;
+	int k, note_played = 0;
 	double audio_res;
 	double audio_curr_time;
 	double res_to_samples;