Selfie Expression - Mouth tracking issues

Hello!
I am experimenting with the Selfie Expression feature. It works rather well so far but I am struggling a lot with the mouth tracking.

VRC seems to think that I have my mouth permanently open and it makes my avatar look rather dumb.

I can disable the eye and eyelid tracking but the mouth I cannot disable. It is also odd-looking when the mouth-tracking combines with the mouth movement when I use the mic.

Anything I can do to disable the mouth tracking? At least when I have my mic enabled?