Can be quite a normal thing if your transducer is in the 1-10kHz range. Did you end up going with a shoot thru install? I remember you weren't sure what way you wanted to do? It's not a good idea to run them while out of the water due to the vibratory backlash on the transducer unit. Are you hearing it only while out of the water?
Is it in the hull or mounted on the transom? What sonar do you have?
It is more common to hear Lowrance than other models.
A transducer is a piezoelectric device, that vibrates when signal is applied and produces current when vibration is applied. With sonar a transducer is a speaker/microphone combo, what you are hearing is the speaker cycle.
383 is a 200K/83K sonar. Should be fine, still it is unusual to hear it while on the water with transom mount. Go in to the menu (most likely have to hit menu twice and make sure it is on sonar tab) and select sonar freq of just 200 and see if you still hear it, then select just 83K and see if you hear it.
It will tell you if there is an issue with just 1 freq or not. If the sonar works fine in all modes and you hear the click in all modes it is just the way that TD sounds. If you do not hear click in 1 frq or the other and there are no sonar returns on the screen you know the TD is bad.