2016a editor "pings" me every time I switch to it.

Every time I Alt-tab to the MATLAB Editor, or if I switch tabs within the Editor, I get the highly annoying warning bell "ping" from my PC. There is no visual indication of any problem that MATLAB is trying to warn me about. Apparently, MATLAB just wants to let me know that it has done what I asked it to do (show me the file). This is new in 2016a. How do I turn this off, and why is it happening in the first place?