2011 Chevrolet Equinox - Battery drain

The battery keeps draining on my Chevy Equinox. Apparently common for this model. If you let it idle it starts to get problems you experience from a low battery. Sporratic in symptoms and didn’t start but if left to sit for a while then will start up. Mechanic replaced the bad battery and a few days later it is starting to do the same thing. Is there any way to fix this parasitic battery drain?

the voltage drops below 12v when idling?

The alternator needs to be checked out if that hasn’t been done already. I would assume the tech that replaced the battery did that at the time but it may not have been done. If there is no issue found with the charging circuit then a normal parasitic current drain check should be done to see if the problem is happening while the car is parked. You seem to indicate that isn’t the case though. Usually fuses are pulled one at time while watching the current drain to help pin down the circuit with the problem.