The lid is literally banging up and down spin cycle starts

We have a Kenmore Elite 110.20952992

During a load today it started making a loud noise. Went in to check and the lid on the washer was literally banging open and closed, the lid lifting a foot or so each time. The washer itself was standing still and vibrating, but it wasn’t walking or anything else - just the banging lid. The load appeared to be balanced, but I rearranged anyway and restarted - same thing happened as it started to spin up, the lid started banging open.

I tool the case off. All 3 suspension springs and the counterweight spring are attached and unbroken. Not sure what to test next? Thanks in advance.