Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Defective Manufacturing

I have Pulmonary Fibrosis and read a review that stated this dvd helped improve breathing efficiency. I have ordered about 10 of these dvd's now from different places.... none of them work correctly. They work for about 2 minutes and then skip and drag.... obviously a manufacturing defect. I was hoping to get one that worked so that I would be able to improve my breathing. Luckily I have been able to return and get refunded for each of the dvd's I purchased. My advice.... dont get your hopes up like I did! I have been dissapointed several times over this dvd!