Same here, my original problem with Amazon Prime Music is back after the latest Brave version update…just never got around to reporting it again.
Problem returned with “Version 0.66.101 Chromium: 75.0.3770.142 (Official Build) (64-bit)” on MacOS 10.14.5 “Mojave”. Was OK with “Version 0.65.121 Chromium: 75.0.3770.100 (Official Build)(64-bit)”.
Original thread: "Amazon Music" complaining about old version of Chrome