Like others have posted, started making an annoying sound after just a couple of months.

Unfortunately, it is not worth the loud sound in my opinion and I will be getting a different brand.

The only downside for this product is that it does produce an audible sound due to the mechanical timer

and it’s making an annoyingly loud buzzing sound.

I only noticed the sound once the room was pitch quiet, and I wouldn't really categorize the sound as annoying,

I bought one for my aquarium and it worked great until it started making this annoying clicking sound constantly after a couple months of use

However, after a few weeks the timer began producing a rattling/buzzing sound that can even be heard from the next room and is impossible to tune out

Very annoying, i can hear it while i am watching movies, its an annoying grinding sound.

Upon opening it and installing it, I immediately heard this somewhat soft buzzing sound

They make a quiet sound regardless of whether you're using the timer, but it doesn't bother me.

Never stopped working, pretty reliable, but eventually the timing motor makes an increasingly loud grinding/buzzing sound after only a couple months that is quite audible even across the room

, it’s accurate and easy to set and functions without maintenance for as long as you’d want, although after a few months of use it has started to make a very annoying sort of rattling sound from the inside of the timer dial, I do believe this is a defect with many Basing my theory from other reviewers posts

After I received the timer I noticed that it was making a strange annoying sound, and the timer wasn't accurate, the customer service contacted me to see if everything was fine and I told them about the problem, they sent me another timer right away!, unfortunately the second timer wasn't accurate as well but the strange noise was gone, I was contacted by the customer service a third time and I told them what's the problem, they sent me a third one which they have tested, the timer wasn't accurate for me, I've noticed that every hour in real life is approximately 45 minutes in the timer, after they contacted me the last time, I told them that the timer has the same problem as the other ones, they gladly refunded me which was really nice of them!

The timer has a constant humming/ticking sound that is really annoying.

It does make a sound like a running filter, but it is not any reason to skip on purchasing this.

The only problem is that it has developed an annoying vibration/rattling sound that never stops, and it really gets on my nerves.

This surge protector works as advertised but constantly makes a dull grinding sound, presumably caused by the rotation of its dial