HTC Pure / Diamond 2 - Bluetooth Noise

I recently got my 2010 Prius V with Nav. I have some strange noise the person on the other end hears when using my HTC Pure (Diamond II) via Bluetooth.

Some details:
- BT Audio streaming works perfect
- A LG Shine has no trouble at all
- The HTC works well paired with a different BT set
- The noise is kind of random and does not stop when the car micro is muted but stops when the phone is muted.

I attached a sample of the noise recorded from the other end of the line. The car was parked in a quiet place no background sounds at all.

Has anyone ever experienced this? My next step is to try the HTC at the dealer at a different Prius.

Anyone with the same phone / car combo?

jakman