For what it's worth, my reply from "Q" was a little different. I'm not positive that his/her email makes sense with the whole "transient protection system" but I do use a power conditioner and I think my cabling is reasonable. Whenever I power off, it sounds like I'm plugging a guitar into a cranked Marshall. It seems to me that if the monitor is the first thing I turn off, it shouldn't pop.
Here's the email:
Greetings from Event Electronics!
Hello Chip, and thank you for supporting Event Electronics. I just wanted to respond to your question regarding the popping of your PS6 monitors on power down. I can suggest a couple of things. Firstly I would suggest taking a bit more time when turning off your gear in your studio. The PS series monitors are equipped with a pretty good transient protection system, however once it has been tripped (most usually by another device or the other monitor) the protection system needs around 40 seconds to reset. The other thing I can suggest is to use a power conditioner/power strip to power on and off your monitors. This can sometime really reduce the transient strength that gets sent through your system. Also, sometimes some better audio cables can really help eliminate unwanted noises from your system.
Almost never has this problem actually been the cause of any type of problem with your monitors. So I wouldn't really worry too much about this. Just be careful not to put your ears right next to the monitor when you are powering on/off the monitors!
Cheers!
-Q