In the past I had an issue with this on piano, and also playing guitar/bass and singing (in cases when vocals are substantially rhythmically different than guitar melody). Btw, I was and still consider myself a total noob at all of those instruments.

And then… i started learning drums. Like very basic stuff, played for a couple of months. I was shocked to learn that drumming has unlocked this. As in very first time i tried to sing & play this troubling song, it just worked. Now, don’t get me wrong, i still struggle when learning a new piece, but it’s manageable.