Alarm going off... RANDOMLY!? '21 Tundra

So last night after about a 2hr drive back home I pull into the driveway, lock the truck, and all is well.

After a couple of hours all of a sudden the truck's alarm begins going off. My response is of course "who's breaking in". After about 10 seconds the alarm just turns off by itself. I race outside, and find... Nothing. No evidence of tampering with doors, windows, etc. After myself and a neighbor scour all over it looking for anything we break and go back to our respective evenings.

About 2 hours later - Alarm is going off, AGAIN. Before I am even fully out of bed the alarm turns back off by itself, again. I walk outside this time with tools in hand. Scour all over the truck looking for signs of attempted entry with nothing found. I pull the negative terminal so that I can get some sleep.

Thoughts on easy places to start? Still dark here so I will mess with it once the sun comes up.

Truck is a '21 Limited Crewmax. Do these trucks have any alarm other than forced entry alarms?