Slam to each connection and standby

This product has a defect size: when the transmitter (my phone in this case), connects to it (very simply by the way!), A "CLAC" very unpleasant (for extremely strong) is heard, a like when you plug a jack on a lighted amp.
Then during use, if no sound is emitted by my phone (time to launch the music player, for example), a new "CLAC" appears as if he would in short standby. The "CLAC" is getting to hear when a sound is emitted by my phone. For comparison, I do not have this behavior, nor with my bluetooth headset, or my car radio.

Perhaps it is a manufacturing defect?