IPhone – Will the new iPhone 7 be compatible with other wireless headphones

I had this exact problem with a 4S until today. Here is what I did:

I installed Skype and Google Hangouts on the 4S to check whether this problem occurs with any calling application or just GSM. I made calls with Skype and Hangouts via WiFi and had no problem at all.

So I had a friend with a 4S with no such problems and I borrowed his SIM card for a test. I called his number on my 4S and had no echo problems! I put mine back and the echo returned. To make sure, I repeated this a couple of times. My SIM had echo, his no echo.

So I went to my provider's shop and requested a new SIM. Problem gone.

I hope this helps people who have tried all else with no results. Why the SIM caused this is beyond me.

My understanding is that you must be on your computer to select which media you want transferred to the device. After manually dragging media to your device or setting up what should be transferred under the correct tabs (i.e Music, Videos, etc.), you must then initiate a sync. I believe wifi sync to be, in short, the same as a USB sync, only over wifi instead of USB, minus a few features such as restoring a backup.

One note - you have probably already figured this out, but after your phone is plugged into USB, don't eject it, just unplug it. Wifi sync will work properly if just unplugged and not ejected.