Volume too quiet on phone calls
When receiving phone calls on my iPhone 6 plus the sound is too quiet. Volume is turned up full and the mute switch on side is NOT showing red.
Is there anyway to boost the volume other than putting it onto speaker which often means the caller cannot hear what I say?
Thanks
Rick
iMac, OS X Yosemite (10.10.1), Macbook Air, iPad, iPhone 6 plus