Thanks for the tip, not sure if it corrected the issue since the ad notification shows up occasionally, but your tip brought me to this....two places in the settings on the general tab that pointed to two connect suspects....hope that's it, thanks.
I see Connect in both places , Settings , Apps , Apps & Features , and in Control Panel Uninstall listed as : Connect Magix Software GmbH version 2.6.1.117 , 15.1 Meg byte . 2018 Premium ads pop up upon close , once in a while , but not every time MM is closing . MM Premium Never pops up ads while MM is in use .