I’ve noticed that a popular google search has been about powering down a Profoto pack. I understand why… it’s not like a light switch, where you flip it on and off. This is how I power down my Profoto 600r AcuteB packs: I quickly press the power button once and let go, then I press and hold it until I see the pack power down. It only takes a moment to do and it works every time. My guess is that Profoto designed the strobe pack this way, so you wouldn’t accidentally turn off the pack by hitting the power button.
Dallas, TX based photographer