Reduce audio latency by using 1K samples instead of 4K.

src/audio.cpp

@@ -24,6 +24,6 @@
 
 void Audio::Setup(int channels)
 {
-    Mix_OpenAudio(22050, AUDIO_S16, channels, 4096);
+    Mix_OpenAudio(22050, AUDIO_S16, channels, 1024);
 }