The problems you have described would be very irritating. Let's look into the together.
When did the issue start after an application was downloaded? Did you recently put the device in a case? Is the bluetooth feature active? If so, please turn it off. Please plug in a corded headset and remove it. If your still experiencing this issue try a soft reset. Here's how: http://support.verizonwireless.com/clc/devices/knowledge_base.html?id=47670
Please let me know if this issue continues.
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