Micromax Informatics — Issue regarding the very low voice of phone

Address:

Gurgaon, Haryana, 110092

I purchased the micromax phone X699 having the Item ID:[protected] on 27th January 2016 through eBay and got the phone around 31st Jan 2016 but facing the problem of very low sound. All my relatives complains for very low volume sound. I told eBay to return or exchange the product but eBay replied me to get the DOA first. Then I went to the micromax customer care for getting the DOA. They refused to give me the same and checked the phone after that. Their engineer checked and told me that this is the highest voice of this phone. And making us fools by saying that voice is good. But this voice is very low as compared to other mobile phones.
As I am facing problem and this is not appropriate for me to use this phone. So please give me the DOA or exchange the phone with any other model.