Green Gremlins is what we called this kinda stuff long ago in the MacPlus daze
It is NOT POSSIBLE that they did anything remotely...
The ONLY event between no joy and joy is the reboot - thus, cause and effect.
However, your issue also involves "cabling" does it not? You have to connect, disconnect, connect, etc. a bunch of times too. Possible that the port had some junk in it and the issue merely appeared coincidentally with the iOS 10 upgrade (I am NOT a big believer in coincidence) - the repeated plug/un-plug may have dislodged the gunk (I give that about a 5% chance of being true)
I suggest finding some solid hardwood furniture and knock on it repeatedly to ensure continued good fortune 😉