Since our company switched from the 4s to the 5s a few weeks ago. many of us have complained that the call quality is pretty bad. I use a LG tone pro bluetooth headset and works great on other devices, it actually sounds good when i play music from the 5s. But when I make or receive calls via bluetooth or handset, the quality is muffled, scratchy, sounding like in in a tin can. The other employees that received the phone have also noticed the issue, they use a motorola bluetooth earpiece. It almost sounds like a poor codec or bandwith issue. Ive even switched from LTE back to 3g but still see the issues..any ideas?