They were doing it on the 22nd & 23rd while we were there. I can deal with the announcements (can't even make out what they say as it's broadcast out in the halls) and the prelude sound, but the high pitched chirping just irritates me like the world's most annoying alarm clock. (If I were sleeping when this went off I guarantee my reaction would have been to throw a pillow over my head and continue sleeping... not the reaction I should give it, but point is, I'm a sound sleeper and the tones are easily tuned out with just a little effort) I was holding my hand over the alarm in the room just to muffle the high tones (it works if you can reach it)
Also, in the community center you don't get the chirps.