Faulty dstv Explora 2

We bought dstv decoder explora 2, from last year it keeps on freezing, no catchup sometimes, and they advise to format the hard drive, we did that and it worked few months and go back to freezing and switch it self on and off and it stack on loading we had to take it to theultichoice center and they couldnt able to help us and they say we must get the new one without telling us where is the problem, so am worried that let say we buy the new one which means after a year we will be having the same problem and i think Explora 2 decoders are faulty n dstv must take full responsibility to give us the new one n accept that these decoders are faulty n fix it, now paid subscription for nothing bcs we can't watch the tv now. And it difficult to explain to my 3 years daughter all this. And i hv seen soany people complaint about it