HI OlegnA,

I am using the TK22 but not with airsoft. I think you don't have to do anything, just connect the airsoft unit to the TK22 (do the mod in the Clark site for the airsoft if you want), As long as a speaker is connected to the TK22, you will hear the main gun firing sound regardless of whether the airsoft switch is on or off. I say that because I can test the TK22 sound even without the turret connected. You will need a hobby grade radio though.