I had the same issue and didn't catch it until I went for a run and the armband applied pressure to the back. Call Sprint and they will send you to a repair center. It is a defect and they will have to order you another phone. Only issue I has with the exchange was Sprint's $35 charge. Since I caught this on day 20,they told me my options were to send to HTC directly and go phoneless for a month or pay. I ed to about 9 different people in three departments including retentions before someone finally caved. My Gid, it was a 20 day old defective phone and I had to pay? Seems like the insurance is quite the profit center for them as it was brought up on every conversation.
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