diff --git a/Makefile b/Makefile
index a4254bb..d3c768f 100644
--- a/Makefile
+++ b/Makefile
@@ -5,4 +5,4 @@ run: compile
 	./z80
 
 debug: compile
-	gdb z80
+	gdb -ex run z80
diff --git a/zx_ula.cpp b/zx_ula.cpp
index 5b3d25b..e7b764d 100644
--- a/zx_ula.cpp
+++ b/zx_ula.cpp
@@ -57,6 +57,9 @@ namespace zx_ula
     static uint8_t ear = 0;
     static uint8_t mic = 0;
 
+    // this variable keeps track of the last "1" written to the sound buffer, so when streaming it in the audio callback, if there
+    // are only zeros remaining in the buffer, we just discard it. It's a poor man's method of keeping the buffer size in control.
+    // This is useless when there are music, sounds, tape loading, etc... as 1's and 0's keep alternating
     static uint16_t last_1 = 0;
 
     void update_zx_keyboard()