diff --git a/zone/spell_effects.cpp b/zone/spell_effects.cpp
index 2a48b9e99..b567bae83 100644
--- a/zone/spell_effects.cpp
+++ b/zone/spell_effects.cpp
@@ -201,7 +201,9 @@ bool Mob::SpellEffect(Mob* caster, uint16 spell_id, float partial, int level_ove
 			continue;
 
 		effect = spell.effectid[i];
-		effect_value = CalcSpellEffectValue(spell_id, i, caster_level, buffslot > -1 ? buffs[buffslot].instrument_mod : 10, caster ? caster : this);
+		// if buff slot, use instrument mod there, otherwise calc it
+		uint32 inst = buffslot > -1 ? buffs[buffslot].instrument_mod : caster ? caster->GetInstrumentMod(spell_id) : 10;
+		effect_value = CalcSpellEffectValue(spell_id, i, caster_level, inst, caster ? caster : this);
 
 		if(spell_id == SPELL_LAY_ON_HANDS && caster && caster->GetAA(aaImprovedLayOnHands))
 			effect_value = GetMaxHP();