We have a Clip n Go dogwalk. Good quality, but we were also concerned with the ringing sound. I tried a sound-dampening coating, but it didn't help. We ended up stuffing large, thick pieces of craft foam into the channels under the dogwalk to fill up the space (thank you, Nick Sparks), and that noticeably muffles it. The foam has been in there for three years and I don't see dogs having an issue with the sound of the dogwalk. Most of them didn't seem bothered by it in the first place, but we didn't want to worry that occasional dog that would be sensitive to it.
Diane Driscoll