a pf cap shorted and shorting traces from input mosfet check it here ground short nd make beep there no beep in normal condition if some confusion about thorting put below ref volatage of mb in 8.9 v over mb +vcc put below value by power supply some component heats bt cant harm curcuit as ur input voltage below battery volatage as min operational voltage is with along load is 6-7 v of any amp max 6.5 a
max heat component heats remove board ok