diff --git a/src/main/main.c b/src/main/main.c
index f2c93f0..81fbffb 100644
--- a/src/main/main.c
+++ b/src/main/main.c
@@ -70,7 +70,7 @@
   - Look at howto optimise main loop
  */
 
-#ifndef RELEASE
+#if !defined (RELEASE) && !defined (MAIN_DEBUG)
 #define MAIN_DEBUG 1  /**< Enable main loop debugging */
 #endif
 
diff --git a/src/tmr/tmr.c b/src/tmr/tmr.c
index 92e840c..d334b2b 100644
--- a/src/tmr/tmr.c
+++ b/src/tmr/tmr.c
@@ -28,7 +28,7 @@
 #include <re_dbg.h>
 
 
-#ifndef RELEASE
+#if !defined (RELEASE) && !defined (TMR_DEBUG)
 #define TMR_DEBUG 1  /**< Timer debugging (0 or 1) */
 #endif