Hozelock watering system

Hi

 I installed a Hozelock Sensor Controller Plus 25 pot dripper system (product no. 2804) two years ago and connected this system to my domestic water supply via a Hozelock 3 way tap connector (product no. 2250).

 This year, I opened the controller to replace the batteries and closed the casing properly. The system is working except for the noise from the controller which is so loud that the neighbours can hear the noise as the water flows through the controller. The noise seems to be caused by the controller’s casing vibrating as the water flows through.

 Do you have solution to reduce the noise from the casing?

 Thanks

 Paul