NTA, and it’s not likely that your small beeping noise is what’s keeping the baby awake, anyway. New Babies wake up on their own multiple times through the night. They’re just trying to find an outside factor/person to blame because it’s easier than admitting that some parts of having a baby sucks. Which would be fine, but they’ve now gone into the territory of harassing you as an outfit for their stress.

Next time they talk to you, (if legal), record it, and politely explain the measures you’ve explained in this post, showing how you have already went above and beyond for their comfort and that this is where you draw the line. After that, If they block your car again, get it towed.