diff --git a/src/fe/map.c b/src/fe/map.c
index b721b6483efaf9756534c4694ddb8e699a322df6..21de46baa496ade6e54b1b3a5be31aca19c28905 100644
--- a/src/fe/map.c
+++ b/src/fe/map.c
@@ -105,6 +105,11 @@ mapPciModules( CDS_HARDWARE* pCds )
     dacdev = NULL;
     status = 0;
 
+    // initialize dac duotone multipliers/divisors in case
+    // we don't have one or the other of DAC or ADC cards
+    pCds->adcDuoToneDivisor[ 0 ] = 1;
+    pCds->dacDuoToneMultiplier[ 0 ] = 1;
+
    modCount = map_cards_2_slots ( &cdsPciModules ) ;
 
     // Map and Initialize ADC and DAC modules