Users start complaining regarding the poor audio quality of phone calls made through Bluetooth headsets and ear pieces. Users are experiencing distorted and robotic sound, and it may cause by corrupted streaming data through the Bluetooth. Apple has already noticed the issue, and they are working internally to find the cause.
I have been working with a high level support person who has assured me he is working directly with engineering. Apple has very much become engaged in this issue. They have had me do extensive testing of various conditions in order to document and troubleshoot – Source