CE,

If you are sitting at the gate with the APU air on, just turn off the left pack. This will lower the noise level from a CAT IV hurricane to merely that of a tropical storm. This works good during briefings and checklist reading. Obviously you have to weigh the cost of shutting off a pack but the amount of the noise reduction is amazing and unless its really hot, is probably worth it. You can also set up for single right pack when taxiing in.

Scoop