The first time I played, I had to quit after a few minutes because the sounds were very uncomfortable. I'm not sure if it's a bug, but the white noise started very loud, so much that I could barely hear the narrator of the gear exhibit. The high pitched sound when a wall is in front of you was also very uncomfortable and aggravated my tinnitus. I think rather than varying the frequency of the sound, you could choose some compatible pitches (a musical chord) and only vary the volume. This would also fit well with the other musical game mechanics.
But, I turned down all those sounds and gave it another try, and I'm glad I did. The musical navigation system of rising and falling notes is brilliant. The robot sounds are very well implemented and do a good job of communicating their position and state. And the narration of some exhibits are pretty amusing if you stop and listen.
The musical hacking game is okay, but I was very confused the first time. I thought I must have been caught in some kind of trap because I couldn't move, but after reading the README again I realized what was going on. I think the 3 by 3 grid is a bit too complex to navigate, remembering where in the grid you are while also trying to remember the tune. Maybe just 5 notes would be more manageable, so you could press the button while holding up, left, down, right, or no direction (center), without remembering grid position.
Overall, very well done, with just a few bugs and issues to work out. Nice work!