Chosen Solution
I have a strange problem where If I ring a person then I can hear them fine but they cannot hear me. However this only applies to this specific number as calling other phones works fine. This problem gets even stranger due to the fact when trying to test for causes the problem actually ended up reversing so they could hear me but I could not hear them, although this only happened once. Finally to add to the strangeness the problem on two separate tests resolved itself only to then return during the next call. When I speak to the other caller if I speak quick enough they will hear me for perhaps a fraction of a second before they can no longer hear me. Both phones are not in silent mode, neither have blocked numbers or call forwarding and both phones are capable of receiving calls just fine from other numbers It’s only when these two phones try to ring the other does it happen Phone 1 is an I-Phone 8 on the Gifgaff network Phone 2 is a Samsung S7 Edge on the PlusNet network
I got lost when you added a second phone to the picture, it gets more confusing than else. However, if I understood correctly that you have an issue with a specific one and only phone number, it’s likely not an iPhone issue. Hardware faults show up irrespectively of the numbers one dials. Either it’s a software glitch that would likely be fixed with a restore, or it’s a carrier related issue. You can try first a network settings reset from settings/general or a full factory reset. Other than that I believe the problem may just be outside the iPhone.
