So, my 2016 nTB MBP started doing this a couple of days ago, it's system wide. I've tried everything I can think of such as resetting P+NVRAM, checking the drive for errors and doing a clean install of Mojave. The issue is sometimes fixed by restarting the computer, but then after another reboot it reappears. It sounds and looks like a button or two is continuously being held down causing the feedback sound and causing it to bring up the search and replace menu (in word) as well as wanting to franticly input the letter "I" and suggesting words to replace that with. As one can see it doesn't keep inputting letters when I type something into the search field of launchpad for instance. The problem was also present when I booted from a USB drive instead of the computers internal SSD.
The computer has not been subjected to any spills, drops or anything else that might cause a mechanical error and since the issue disappears after a reboot it would seem like something else is going on here, but I have no idea what that is. Any suggestions?