Well, I did not want to get into it, but it's easy for me to explain.
I use a Samsung Galaxy today, but I have used Motorola's, and Blackberry as well...All these phones, certainly made calls and received them, but when it comes to most Apple phones, I can tell when someone is using one and calling me because I have great difficulty understanding what they are saying. The quality is tinny and they sound as if they are in a trashcan.
In terms of signal ability, the Apples are also slightly inferior as I have noted many times that I can make and receive calls when they cannot and on the same provider....and I have not even got to the battery issues..
So there ya go...that's my observations..
I haven’t had any of the audio problems you describe. I live in NYC metro area so maybe the signal is better here than in other parts of the country. But even when I go to Boston or DC, I get a strong signal.