Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Me too :(

Late 2016 15" MPB with TouchBar... The letter "b" has become faulty overnight: I need to click the "b" much more purposely to make it work.

Sigh...
 
make a video of it I would actually like to see this problem. A lot of people talk about double presses but this is very uncommon especially in the butterfly keyboard.

Doubt it's a hardware issue if it's already been replaced.

No I’m not taking a video. It’s a hardware issue. You don’t have to believe me but it’s a hardware issue that has been widely reported. I sent it off for repair a second time and it’s good now but my space bar sometimes repeats. My space bar at work on my 13” work MacBook Pro also has the issue. It’s extremely frustrating that they can’t make a quality keyboard.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.