Toyota Prius 2006 Bluetooth Static Issue

So i have a Toyota Prius 2006 which i have had for about a year now. I know that the bluetooth on this car only supports calling which was fine with me since i have the aux car. However, after a few months when i connect my Iphone 6s plus when i try to talk to anyone it sounds very staticy. This never used to happen and now it's happening. I did try to even disconnect and connect it back again, but this didn't help the issue. Any ideas of why this would be happening? Thank you!