Anyway I as well had issues getting my camera into the purple light (flash firmware) mode because I was renaming the file with .bin at the end and windows already has the extension on it that step isn’t necessary. I described it quite extensively and even put instructions and a picture of what your sd card should look like with just that file on there. You have to make sure you check the settings when you’re looking at your sd card windows doesn’t by default show extensions you have to turn it on. I’ll link the thread here for you, if you follow that you will get the flashing to work and have audio again just like me TomPickles and Jdonnell.
https://forums.wyze.com/t/cam-v3-cant-get-firmware-to-flash/267890