Before you tear it up, I'd check to see if it is still under warranty.
DATE CODE EXPLANATIONS
Each Plantronics unit is imprinted with a date code to assist in tracking warranty information. The date code can be found on the plastic housing on the top half of your headset or, if your unit is an over-the-head style, the date code is located under the foam ear cushion. For more information you can contact technical support.
Warranties for products last one, two, or three years (depending on the product and country you are in) starting from your original date of purchase or according to your products’ Date Code. For more information you can read the worldwide limited warranty terms and conditions.