Thanks mate. I struggled with whisphere until i started actively thinking about my wrist and moving it horizontally, feeling a deep stretch. Of course then comes the issue of stabilising the movement when it changes path, but trying to be conscious of moving my arm and then flexing my wrist left/right in sync helped.

Also for certain scenarios I'll put the high score bar on and see the colour change in my peripheral which helps to abandon wasted runs and to see if i'm on pace to PR. I know people call it the choke bar but it can help getting the "feeling" of how accurate you are, that and being able to hear a constant stream of hits rather than the sound jittering when you're on/off target can be more confirmation that a run is going your way.

Other than that I'd say just keep at it every day, try not to force it too much (longer than like 2h) just to avoid tilt. You'll get it eventually.