diff --git a/src/sound.c b/src/sound.c
index 51dbcbc..9ab05cc 100644
--- a/src/sound.c
+++ b/src/sound.c
@@ -550,6 +550,8 @@ void voice_update(alVoice* voice, double px, double py, double vx, double vy) {
 
 // Changes the voice's buffer.
 void voice_buffer(alVoice* voice, const ALuint buffer, const unsigned int flags) {
+  if(voice == NULL) return;
+
   voice->buffer = buffer;
   voice_parseFlags(voice, flags);
 
@@ -561,6 +563,8 @@ void voice_buffer(alVoice* voice, const ALuint buffer, const unsigned int flags)
 
 // Stop playing sound.
 void voice_stop(alVoice* voice) {
+  if(voice == NULL) return;
+
   soundLock();
   if(voice->source != 0)
     alSourceStop(voice->source);