Laying down and talking on 5S....

[Gix1k]

For some odd reason people say I sound muffled when I lay down and talk to them. The phone is positioned exactly the same way it was while sitting up...I've tested it..so, carrying on a conversation, all is well. During the conversation I lay back on a pillow, I get told they cannot hear me. I have to take the phone off my ear and hold directly in front of mouth to be heard or sit back up.

 

[PNutts]

Try turning off the noise cancelation:

Settings > General > Accessibility and turn Phone Noise Cancelation

 

[Mrbobb]

You may have a strategically placed piece of lint stuck in there.



or if everything else fails, blame it on you holding it wrong.

 

[Col Ronson]

happens to me with every iphone i use. its the way i position the phone/noise canceling. Your only option is to sit up, use headphones, or turn off the noise cancelling.