LG VX-6100

I have the LG 6100 and also TWO Jabra headsets which I've had for over a year and a half. I used it on my motorola for all this time. Now, in March, I purchased the LG 6100 and just last week, one of my headsets stopped working (I couldn't hear the person on the other end, yet they could hear me). Then less than a week later, my second headset is doing the same thing. I took the phone to Verizon and they say the phone is fine. Why would this happen to not just one but TWO headsets within a week of each other ?? (BY THE WAY..my sister also has an lg phone and this exact thing happened to her Jabra headsets (2) a month and a half ago! Any help ??? Please! I am lost without the headset and really liked the Jabra, but am afraid to buy anot...
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