[SDPhantom]

local AddOnPath=("Interface\\AddOns\\%s\\"):format(...);--  Dynamically fetch our addon path
local EventFrame=CreateFrame("Frame");
 
EventFrame:RegisterEvent("PLAYER_LOGIN");
EventFrame:RegisterUnitEvent("UNIT_PET","player");
EventFrame:RegisterUnitEvent("UNIT_HEALTH","pet");
 
local LowHealthThreshold=0.35;
local LastHealthValue=0;
EventFrame:SetScript("OnEvent",function(self)
    local cur,max; if UnitExists("pet") then--  Check if pet exists
        cur,max=UnitHealth("pet"),UnitHealthMax("pet");
    else cur,max=0,1; end-- Process no pet as dead
 
    if cur and max and max>0 then-- Check if we have health data
        if cur<=0 and LastHealthValue>0 then--  Is pet dead?
            PlaySoundFile(AddOnPath.."Res\\PHA.ogg");
        elseif cur/max<=LowHealthThreshold and LastHealthValue/max>LowHealthThreshold then--    Is pet low health?
            PlaySoundFile(AddOnPath.."Res\\PHA.ogg");
        end
 
        LastHealthValue=cur;--  Update tracking value
    else LastHealthValue=0; end--   Reset to zero if health not available yet
end);