FaceTime failure

When my wife FaceTimes or calls. No audio during calls or use of speaker phone function (in grey). When FaceTiming, call opens- says connecting ,then fails all within 5 seconds. Phone is iPhone 7. Latest software update. Reset network settings. Logged in and out of AppleAccount. Reset all settings. Hard reset. Checked screen time limitations any possible available information and have concluded the motherboard has a failing component. Anyone concur?