Possessed smoke detectors

Okay, so the other weekend I was enjoying a nice night scrapbooking when my smoke detectors became possessed. Seriously possessed. It was the craziest thing ever. You know when your battery starts going dead and it "chirps" at you? Well ALL my smoke detectors began chirping at me in random intervals. And not the normal once every hour or longer. No we are talking seconds between them. Now my house is nice and safe and has 7 smoke detectors. After an entire night I thought I was going to go crazy. I couldn't just run to the store as my sweet husband and oldest son were gone to Las Vegas for the weekend. So after changing the battery in one and pushing the reset to no avail I called a wonderful friend who let her husband rush right over to come to my rescue. He came armed with another battery and a volt tester. He replaced the lowest charged battery, which really wasn't close to dying and we reset the smoke detectors. Seconds later we hear another chirp, then another. I thank him and try to put my kids down for their nap. Yeah, we all know how well that went! Then I gave up and took 4 VERY ornery kids to a church dedication where I was singing in the choir. Yeah, again we all know how well that went. To the credit of my older three they were great for the sweet person who sat with them. The baby, yeah I couldn't even sit on the stand like I was supposed to. I would leave a crying girl long enough to go up and sing then sat out in the hall with her, until time to leave her to cry and go up again. After we finished that I asked an electrician and a contractor for advice. They gave suggestions which I then called my wonderful friends husband to come check the voltage in the wiring in my house while we air cleaned all the smoke detectors. After resetting them the chirping continued. Sending him off again with my thanks I then called my sister, who looking back should have been one of my first calls. She works in UT for the State Fire and Safety and reads and knows every obscure fact about smoke detectors. She however only had a couple new options, which really didn't thrill me. I called the home alarm company but no help there. So at 9:30 I broke down knowing I couldn't take another night of it and took her advice. I called the local fire department to come over and have them figure it out and fix it. (Denise also suggested this but I hadn't wanted to listen to her either). They couldn't come in in a small truck, no we got the ladder truck. So thrilled. Also, four firemen and a paramedic came. The firemen were in full gear, helmets air tanks the whole bit. They walked around my house set off my alarms multiple times. Retried everything we did and a few others. Reset and took each one down and back up. Checked my breakers, everything. After 45 minutes of fun, with Rachel making Harrison sit on her bed with her and never move since it made her nervous and Ellie trying to get each one to pick her up and play with her we had no more answers and still constant chirping. Ellie really was funny with them. I heard multiple times, "No sweetie, don't touch my axe that will hurt you." "Here let me move that tank out of your way, darling" "You are too cute" as they pick her up and play with her. She kept grabbing at their legs and following them everywhere, just loving them. So after they got back into their firetruck and left with a request for us to call them when we figured it out. We gave up and tried to go to sleep through the chirping. John was on his way home and sure he could fix it. A little after midnight they all just stopped chirping. One little chirp about every hour. When John got home he found the small plug in CO monitor with low battery on the screen and said, "This is the only thing chirping, I don't know what you made such a big deal about". I was tired and ornery and ready to kill him. But I have several firemen and Eric who can attest to the craziness of my smoke detectors. Which by the way we never did figure out why they went on the fritz. I just pray it NEVER happens again!!!!