No idea what cause that glitch, really. Maybe I left the window and came back?
Sounds specific to each building is a good idea. Same for having some landmarks like a fountains that makes a noise you can position. Duck pond, playground, stables, whatever has a unique sound.
Different floors with different sounds. Crunchy gravel, swishy grass. Different footsteps sounds could help guide people.
Some times the sound for bumping into walls won't play. That doesn't help either.