diff --git a/src/audio_call.c b/src/audio_call.c
index 85158b9..c4a69a2 100644
--- a/src/audio_call.c
+++ b/src/audio_call.c
@@ -65,7 +65,7 @@ void callback_requ_timeout ( void *arg );
 void callback_peer_timeout ( void* arg );
 
 
-static void print_err (ToxWindow *self, char *error_str)
+static void print_err (ToxWindow *self, uint8_t *error_str)
 {
     line_info_add(self, NULL, NULL, NULL, error_str, SYS_MSG, 0, 0);
 }