While XCode 10 simulator allows to record, save, and play back audio on old models: 5S, 6-8, 6-8 Plus, SE, and X, none of the new models - XS, XR, X Max - record audio. No errors, no warning. Just silent fail.
I had a lucky opportunity to run the app on actual device - X Max - and it worked as supposed; i.e. audio recorded, saved, and played back.
So, it looks like a bug in a simulator.
Igor Borodin
