Problem with air gap faucet installation

I have an upstairs bathroom where I just installed a new TOTO Drake toilet last weekend. No leaks, (I slide cut pieces of brown paper bags under the toilet around the drain for a week to ensure no leaks). What I did notice today was the water level was way down in the bowl. I checked the OF valve in the tank and it's fine. I flushed the toilet again and it's fine and the water level in the bowl comes back up. I marked the level in the bowl with a piece of blue tape and 2 hours later the level dropped about 1/8". I then had my wife flush the other upstairs toilet which sits back to back with this one in another bathroom and noticed the water level dropped about 1/8"?? It appears when the master bath toilet is flushed I lose water in the bowl of the guest toilet. However, when I flush the guest toilet the water level in the master toilet does not go down???? So then I flushed the guest toilet again, bowl water level comes back up and I mark it. 1 hour later it's 3/16" lower and we did not use the water? I none of my brown paper leak strips are wet? What are the odds of a crack in the bowl's trap that just happens to also go directly down the drain and not of the floor??? If it is a a clogged vent, why would the water level drop when not toilets are used? Also, wouldn't the vent issue make the master water level drop if the guest toilet was flushed??? Sorry to be so long, this is frustrating:madhell:

I just changed the gasket (splash guard) on my ISE disposer. When I plugged it back in, it started running. Wall switch has no effect. I had to unplug it to turn it "off". What happened? Thanks, Mitch