In 20w46a (and 20w45a), chest closing sounds for both regular chests and ender chests are no longer synced up with their respective closing animations like they were in 1.16.4. It should be straightforward to reproduce, just open/close either a normal chest or an ender chest and the bug should occur.
I feel that there are two ways to fix this bug, either delay the closing sound a little bit just like in 1.16.4 or immediately play the closing animation when the player closes the chest (I think the second solution might be the best solution, and probably the easiest).
Video: https://youtu.be/r2OAtIpaQzU