ADDING A SOFT ON/ OFF CIRCUIT TO A UNIT

Hello, I have a question... It seems rather simple, but maybe not.
I have an electronic Crossover unit from DBX that is very good, does what I need, and really is necessary for my system.

However one downfall is it does not have a soft start/on/off type circuit for power up and down..
It will let out a pretty good thump, and or squeel once in a while... Now I know what most answers will be, Turn off your amp first stupid!!

Of course this works, but is not always remembered, or could loss power, or even accidental power chord pulled, or button pushed...

I know the DBX WAY higher cost unit has a Soft Circuit.. But I have ZERO use for that unit in my application, and don't feel like paying another 1200 to 1500 to gain just a Soft circuit..

Basically the question is how to get one in there.. I know Tons of Power amps, And preamps, And several other Standard A/C powered units have these capabilities, and would like to find someone that might have an idea to add this to block the signal on power up and down without current limiting the unit or degrading the sound of course.

Might be simpler said than done, I don't know, I have heard of Bridged capacitor across the Power switch terminals etc... Or something to this effect to supress the residule signal etc...

I have no idea the safest way to go about this.. Its a DBX Driverack P.A.

I have called a couple of the Bigger mod companies mentioned on this site, like Underwood & Modwright, but they have no interest in doing this, and if they did it would cost basically what doing a full mod would.. which on their estimate could cost about 1000 bucks anyway!

Please advise,
Thanks!