Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Sound is fine for my ears but product design unworkable

I sought out a2dp headphones and have owned this product for a month or two and use it with a Treo 680.(1) Never had a "necklace" style bluetooth and, while I'm trying to get used to it, the little plastic pieces that make the "rope" into a necklace BROKE.(2) The thing keeps shutting itself off after 5 minutes of use -- enough to make me want to return it. JUST AFTER the 30-day return policy.(3) Even after adjusting the earbuds to fit, they fall out of my ears after 5 minutes.:(