We purchased a new phone for our daughter at Verizon last summer. The phone quality was never right. We purchased the same for our son that same week and all is perfectly fine. Since then my daughter has made many trips to Apple, assuming it was something with the iPhone X. After tweaking settings and software, nothing changed, so Apple gave her a brand new iPhone X. There was no change in sound quality at all, so this seems to be a Verizon issue. She puts her phone on speaker at a low setting because it is often impossible for others to hear her any other way. It fades in and out. Sometimes her voice is completely inaudible. Our daughter is a grad student, applying for jobs, and sometimes these are cross country, so interviews are conducted on the phone. What was once an annoyance is becoming a very serious problem. Please advise.