Midi Editor - note input sound

I don’t know what has changed in my Midi editor… I have noticed there is no sound of the midi note played when I use the down or up buttons in the transpose indicator at the top toolbar section. Is there a box to check off? I looked in the preferences - nothing I recognized there and also in the Midi editor - any ideas what to do?

Is this button turned on?

Yup! It’s when I use the up/down buttons at the far right that it doesn’t work. If I move the notes with the mouse it works fine - but not with the transpose buttons.
Midi transpose