Mouse pads work for me---buy used ones at garage sales and use as many as I need to fit the machine and serger

I agree with all of the above on padding and a sturdier table. Back in the day, I had a card table as my sewing table. It really did the jitterbug when I sewed, especially when I went at a higher rate of speed. When I was able to move to the dining table cuz the little kiddoes weren't as curious anymore, it was a great improvement.

If your machine is sitting on a table, try to move the machine closer to one end or the other. The legs being closer to the machine will help a little with the bounce, and slowing down also always helps

You can also place a piece of plywood under the machine and on top of table, That might help also.

I put a flat piece of board on my table for my portable. If it's on a level piece of furniture with absolutely no give when you lean on it you're good. Last night I needed a bit more room so I put my 401 down into the cabinet then my portable on top. Didn't bounce at all.

An old wood cutting board works great, also!

If you check with your local carpet store, they have samples of their different carpets and they have a binding all around the square of carpet. (actually a "rectangle" of carpet) When they get new samples in the store, you can usually get them free or once in a while you see them at flea markets for 50 cents or $1 ea. They are just the right size and the carpet thickness holds your pins like a pin cushion, and keeps other items like snips or scissors, handy as well and looks neatly organized. When I sew full speed ahead, nothing bounces anywhere. And the carpet samples look pretty under the machine too. (get a pretty one to match your sewing room) Sandrea