iTunes RequireAction failure:

I recently upgraded my MacMini to High Sierra. I have the iTunes plugin installed and loaded. I now notice in Console, whenever I play music from iTunes, the error message:
"iTunes RequireAction failure:" repeated every second. Music plays fine despite the error. Error messages keep going even when iTunes is being paused. Error messages go away when I restart iTunes until the next time I play something.

When I disable the iTunes plugin those error messages do not appear while playing music.
I re-paired the iTunes server remote, which did not help.

I also get from time to time those debug messages:
iTunes Debug statusThread.run(): server unavailable - retrying in 12 seconds

[jay (support)]

Yeah, no idea. We are using a low-level reverse engineered library in that plugin which I expect will break someday (it did for a while in Catalina's Music app, but it appears to be working again). If it's working, I wouldn't worry about it but it's not something that we're going to pursue.