I bet you have a slot glide on the front. I only do that on residential. I use hybrid and hole glides on cgd. With approaching 2million sqft on my 15” and 17” zippers I haven’t had a chatter since pulling the slot glide off my 15”.I just got the zipper wand and I’ve been having difficulty with it. Almost every glue down carpet I have done it bounces on it. Sometimes it’s just 1 direction sometimes both. Sometimes it’s very difficult to push and other times difficult to pull. I have tried adjusting the height and it seems adjusted correctly. There has only been few glue down carpets that it doesn’t bounce. I feel like I wasted $2300 now. It’s very frustrating to see it bounce constantly. Anybody else have this problem ? Any suggestions would be appreciated. Thanks.