Here’s another one I had (this was a while back, actually). I was in a school, supposedly during a fire drill, and the alarms were Simplex SmartSync TrueAlert horn/strobes doing code-3, but the pitch of the TrueAlerts were unusually high (they were about the same nominal pitch of a -9219). Also, I went by a 4603 annunciator, which seem to have been already acknowledged, since I didn’t recall hearing it buzz.
Also, going a bit off topic, but I’ve created another topic that’s exactly like this one, but not relating to fire alarms: <URL url="Dreams/Fantasies in General]. Feel free to post any non-fire alarm related dreams you had in that topic.