@MikeK - Did you get this resolved? I just was having the same issues and your post helped at least figure out WHAT was happening. On the main laptop screen...button triggers immediately. But if i move the spreadsheet to an extended monitor, it doesn't trigger unless i hold the mouse down on the button for about 4 seconds.

Thank you

Edit....more googling and i found a solution that worked for me. Bottom right on display settings, change from optimize for appearance to optimize for compatibility.

solution came from this link https://answers.microsoft.com/en-us/msoffice/forum/all/command-button-macro-not-working-when-on-second/61da5773-29cc-4701-b065-3ddc5e0d8c1b