First of all, I would strongly recommend against using any amplifier as powerful as the M200 for tweeters. These drivers need much less power than the midrange and woofer drivers. The ideal power level is 1/2 to 1/4 of the power of the woofer amplifier.

The trainsients you hear could either be generated by the power amplifier or the active crossover network. In my system, the active crossover generates a turn-off thump so I designed a timer which keeps the crossover powered on for a minute or so after the power amplifier turns off. This eliminates the thump since I use vacuum tube power amplifiers which still pass signal for several seconds after power is removed.

Some power strips include timing functions in addition to power line filtering. Other members might have some specific brands

I would dis-connect your crossover from the power amplifiers and cycle the power to see if the cause is the crossover or power amplifier.

If it is the power amplifier, a method I have used in the past has been to place a non-polar capacitor of high qualiy in series with the tweeter's "hot" lead, and choose the value of the capicitor so that the cutoff frequency is between 1/4 to 1/2 below the crossover frequency of the active crossover to the tweeter. For instance, if you use a 2kHz crossover to the tweeter, choose a capacitor that causes a high pass frequency of betwen 500Hz and 1kHz.

This high pass capacitor will keep low frequency information generated by a power amplifier transient from reaching the tweeter. The high frequency transient information that remains is unlikely to do any damage to a tweeter.