When using the Reply function, the audio source must include the target to be replied to. For example, if Beltpack A calls Beltpack B, and Beltpack B needs to reply to Beltpack A, Beltpack B’s audio source must include Beltpack A. If Beltpack A’s call target is a group, Beltpack B’s audio source must have the same group membership as Beltpack A. If Beltpack A’s call target is eltpack B, Beltpack B’s audio source must include Beltpack A.