Hyundai Motor India — Music system - cheating

I am an advocate. I purchased eon era on 4.6.2016. At demo and booking time dsc nandanam assured music system as that of eon magna but during delivery fitted with xenos set without antenna which earlier agreed by ticking in list. There is fluctuations in sound, horrible to hear. Complaint many made, one to mrs. Gayathri and sridevi, though assured to set right did not turned up. Umashankar