Hi, @Ken1. I’m the person the created and shared the macro. Sorry to hear that you are having a problem. (Thanks, @tiffle, for your troubleshooting efforts!)
I suspect I know the cause of the issue but I’m away from my Mac so I can’t confirm my suspicion. In the meantime, please try downloading the add-on macro that can be used to toggle between two settings.
In that macro you will need to enter two of your sound outputs. You can then set a hot key for run THAT macro. I suspect it will work. Do be careful entering the sound output values. It can be tricky if the items include an apostrophe.
When I return to my home, I’ll troubleshoot further. I think it will be a trivial fix.