Jawbone Bluetooth headset - Discouraging

[Neville310]

I recently purchased the Jawbone Bluetooth headset from the Cingular store. The reviews looked promising and noted its advance noise reduction technology. My initial impressions were good from the packaging, the design, and general fit. It flawlessly paired with my Treo 700p
Unfortunately, several callers have mentioned that my voice sounds like audio in a cave or elevator. Others asked whether I was on speaker phone or why was my voice low. Basically, these calls were in non problem areas (full signal strength and no ambient noise). Calls were placed in my home and sitting at my desk. I have not tested the headset in all conditions, yet I already had thoughts on returning the headset. It upsets me since I did research the product and read several stellar reviews. The headset is just costly for less than stellar performance.

Maybe, I overlooked some settings on the Bluetooth headset or Treo. The Jawbone does not completely rest on the voice activation button. My face is angular and triangle shape, thus the sensor barely touches my cheek. This scenario may cause less than stellar performance, yet I have not intentions on plastic surgery; I will opt for another Bluetooth headset.

So I wanted to get feedback from other Treo users, who also purchase the Jawbone headset, before it goes back this weekend. In addition, I would like recommendations on other bluetooth headsets with stellar performance since this purchase represent my second Bluetooth headset. I am looking for better performance than my Plantronic 640. Can you use two headsets with the Treo 700p (initial tests have not worked for me)?