Samsung home theater system started showing fault

I bought a Samsung home theater system axactly 7 days ago and two days later the home theater system started showing fault,it would play and shut down on its own. Upon arrival at the store my husband and I where told it needs to be sent for assessment. This is a system that is only 7days old and it already has to be repaired if there's any fault found. The invoice stated that the goods should be replaced or client refunded if there's anything wrong with the product. After being promised that the complaint will be resolved by the end of the day there's still no communication or update regarding the complaint. Bad service Samsung Cresta.