Setting airplay password

The AirPlay password is set on the AirPlay receiving device.

For the modern Apple TV box, that is in Settings﹥AirPlay﹥Allow Access﹥Require Password﹥

The default may be obfuscated (••••••), but can be replaced by anything else, or the requirement can be disabled.

It is randomly generated each time so there is no way to set it.

I hope this helps!