Live shows on air: Playing an instrument on radio.

[Kotlol]

I personally would not want this in the game because I find instruments loud and annoying.

Not that it's a bad idea. Maybe a cool down like you suggested would be fine.

My sentiment exactly.

With musicians I can kill em or get away from them or take away their weapons. With the radio I have to turn it off.
With this.. I am not sure...

In my opinion playing instruments on the radio is a good and logical idea. But insted of a cooldown...
Let's use the advertisment tape.

You plug the instrument into the reciever and you have x amount of time before the instrument "overheats" and breaks.
It won't count as your song cooldown, but in doing so you expend the instrument. This is all to avoid players spamming the same music over and over and makes buying multiplue instruments have a goal.