Dreaded air dryer problem...

We've all had to sleep next to a truck with a repetitive air dryer pop off. It's enough to drive anyone crazy. I just moved into a 2015 Mack Pinnacle and it seems as if the air compressor is continuously running. Nobody is in the shop today (Saturday) for me to ask, so I was just wondering if this is a common issue. Also, when it pops off, it's not just a "pshh" sound, it's more like a long "whoooooosh". Very loud and obnoxious. I don't notice the air pressure dropping by looking at the gauges and don't hear any external air leaks, and it occurs both bobtail and with a trailer connected

 

I let the truck idle for a bit and listened for leaks. There is no air leaking after it "pops" off, but the compressor stops, then kicks back on about a minute later even though the pressure barely dropped

 

What is a wet tank?

 

Is that why there's 3 cans in between the steps?

 

Yeah repairing it is way out of my league. I just like to have all my ducks in a row on the write up slip so the mechanics don't think I'm an idiot lol