I did report this bug some time ago, but may not have supplied steps to reproduce.
There may be more be a more simple path to reproduce, but this is how it regularly happens for me:
* View: Show Art with Details. Open the artist album node, and navigate to an artist with quite a few albums
* Open a second tab. View: Show Art. Show Column Browser. Sort the view by Rating (ie. numeric)
* Return to the first tab, and the loop will start. If the first tab had been positioned at, say, "Miles Davis", the repetitive dbox would be complaining that "M" is not a valid integer.
On some occasions you only have to "OK" the dialog box a couple of time and the cycle stops. But if the left or right hand side has a lot of entries (not sure which) the cycle seems endless, and you have to terminate MediaMonkey with the task manager.
Let me know if you can't replicate, and I will try and refine these steps. ... It happens to me several times every week.

I am running the latest, ie. 4.1.12.1795