Audio and microphone suddenly stopped working on iPhone 7

My audio and microphone suddenly cut out on my < 2 year old iPhone 7 yesterday. When I try to make phone calls, a connection is established but I cannot hear the people I am calling and they cannot hear me. I've done everything that the Apple Store, and tech support has told me to do including updating and restoring my phone to factory settings to no avail. On another forum posted in apple communities I noticed that over 3000 people have had the same issue and yet Apple refuses to admit that there is a recurring problem with the iPhone 7. An authorized apple repair store that I spoke to even said that it was a problem with the phones motherboard, and many online forums have said that it is a problem with the audio IC chip in the phone. Has anyone who's been outside of the warranty period on the phone been able to resolve this issue without having to completely replace the device? I've spoken to multiple people at Apple stores, Apple tech, and apple customer service to no resolve. I've been a customer with Apple for over 10 years and have owned many iPhones, Macs, iPods, and iPads from them and this was a huge deal breaker for me. This will be the last purchase of an apple product for me: I can't gamble 1000$ on a phone for it to last less than two years.