Very interesting take on the theme! Using the walls to move around was interesting, but like a few other people said here, it would be great to have a more accurate measurement of how far "one step" is. I was't even aware that you could move in 8 directions insted of 4 until I read the comments. That being said, I reeeally like what you've done with the sound and how it helps conveying how far you are from the objects.
Keep up the good work!