diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index 0dcd729d..04350a8a 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -1767,7 +1767,7 @@ void FurnaceGUI::drawMacroEdit(FurnaceGUIMacroDesc& i, int totalFit, float avail
 \
       /* if ADSR/LFO, populate min/max */ \
       if (i.macro->open&6) { \
-        if ((i.macro->val[0]==0) & (i.macro->val[1]==0)) { \
+        if ((i.macro->val[0]==0) && (i.macro->val[1]==0)) { \
           i.macro->val[0]=i.min; \
           i.macro->val[1]=i.max; \
         } \