diff --git a/examples/audio_sine.cc b/examples/audio_sine.cc
index 13724bd..3fb9e53 100644
--- a/examples/audio_sine.cc
+++ b/examples/audio_sine.cc
@@ -33,15 +33,15 @@ using namespace SDL2pp;
 int main(int, char*[]) try {
 	SDL sdl(SDL_INIT_AUDIO);
 
-	const int samplerate = 48000;
-	float frequency = 2093.00f; // C7 tone
+	constexpr int samplerate = 48000;
+	constexpr float frequency = 2093.00f; // C7 tone
 	int64_t nsample = 0;
 
 	// Setup audio device, and provide callback which plays sine wave with specified frequency
 	AudioSpec spec(samplerate, AUDIO_S16SYS, 1, 4096);
 
 	// Open audio device
-	AudioDevice dev(NullOpt, 0, spec, [&nsample, frequency, samplerate](Uint8* stream, int len) {
+	AudioDevice dev(NullOpt, 0, spec, [&nsample](Uint8* stream, int len) {
 				// fill provided buffer with sine wave
 				for (Uint8* ptr = stream; ptr < stream + len; ptr += 2)
 					*(Uint16*)ptr = (Uint16)(32766.0f * sin(nsample++ / (float)samplerate * frequency));