I used to have a bit of trouble with sidechaining in FL the standard way, so I've developed my own little method that works well for me and is nice and clear.
I'm not sure if this would work well in other DAW's but it works in FL for me.
What I did, was start off and create two very tiny automation clip, about the size of a 1/8th note and apply one to the mixer channel volume of the synths and the other to the sub bass.
I then right clicked at the left side approx 60% down from where it starts at creating a sort of check mark shape, it looks like this.

I then went into my arrangement window and for each instance of a kick, I had it execute both automation clips, and for the snare I had it applied to the synth automation clip.
This way it cuts out the volume of the synths/sub just enough for the kick and snare to come through nice and clean without waiting for delays when using a compressor.
Hope it works for you! Cheers.