While it is impossible to make a truly silent pet feeder we have worked hard to develop a quiet feeder. The loudest part of the feeder is the door opening which will only occur a few times per day and runs at approximately 55 decibels (equivalent to the sound of your refrigerator running). So far in the homes the PortionPro Rx has been used there has been minimal issues with pets and the noise of the feeder. If your pet does have issues with the noise of the door we offer solutions such as running the feeder in open mode to reduce the amount of times the door needs to move. Other tips are available in our acclimation guide that comes along with every feeder and can also be found here on our website.