How do I disable just the error text and sound?

I'm creating an extensive set of macros to help healing, and the error text "Invalid target" and the sound that goes with it are both incredibly annoying. Please add a feature that lets players disable both of these without disabling system sounds entirely.

Thank you.

I consider this a technical issue because it is negatively impacting my game play and I cannot see a way to solve these issues without a change to the game's code.