I think I must be going a little crazy..... I just heard a very distinctive dial up modem sound.... Maybe 9600 baud.
No radios are on....so it wasn't something sending packet or aprs.
But that's not the crazy part .... No one else in the room heard it, I was the only one.....
It wasnt loud, and didn't last very long. For the life of me I have no idea what would have made the sound...