diff --git a/sa_core.c b/sa_core.c
index 269b745..9f6b124 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -862,8 +862,11 @@ float perform(bool break_on_operation, int i, int32_t f, int tracking)
     } else if (MODE_LOW(setting_mode)) {
       if (setting_mode == M_LOW && !in_selftest && avoid_spur(f)) {
         local_IF = spur_alternate_IF;
-      } else
+      } else {
         local_IF = frequency_IF ;
+      }
+      if (setting_mode == M_GENLOW && setting_modulation == MO_EXTERNAL)
+        local_IF += lf;
       setFreq (0, local_IF);
     } else
       local_IF= 0;
diff --git a/ui_sa.c b/ui_sa.c
index f3b28e6..d50895a 100644
--- a/ui_sa.c
+++ b/ui_sa.c
@@ -12,6 +12,7 @@ void set_refer_output(int);
 int get_refer_output(void);
 void SetAttenuation(int);
 int GetAttenuation(void);
+int search_is_greater(void);
 void set_auto_attenuation(void);
 void set_auto_reflevel(void);
 int is_paused(void);
@@ -43,6 +44,7 @@ void redrawHisto(void);
 void self_test(void);
 void set_decay(int);
 void set_noise(int);
+void toggle_tracking_output(void);
 extern int32_t frequencyExtra;
 extern int setting_tracking;
 extern int setting_tracking_output;