Mixed Munitions not working properly

Bug: Mixed Munitions Notable in combination with Advanced Traps has an interesting interaction with cooldown recovery, resulting in Mixed Munitions being a net loss in cooldown recovery. Upon detonating a mine, a trap with Advanced Traps Support will have its cooldown increased with the first mine detonation, and then begin decreasing the cooldown after the first.

Build:
https://pobb.in/1BSGthnF76QH

To replicate:

Allocate Mixed Munitions.
With Advanced Traps Support equipped to Seismic Trap:
Throw Seismic Trap. Observe Cooldown, for my setup it is 2.0s.
Throw and Detonate Mine:
0 Mines: 2.00s
1 Mines: 2.94s / +.94 ***
2 Mines: 2.89s / -.05
3 Mines: 2.84s / -.05
4 Mines: 2.79s / -.05
~~~
17 Mines: 2.27s

Without Advanced Traps Support equipped to Seismic Trap:
Throw Seismic Trap. Observe Cooldown, for my setup it is 5.0s.
Throw and Detonate Mine:
0 Mines: 5.00s
1 Mines: 4.85 / -.15
2 Mines: 4.71 / -.14
3 Mines: 4.57 / -.14
5 Mines: 4.44 / -.13
~~~
17 Mines: 3.27s

It's worth noting the character stat screen is properly displaying the intended "Cooldown Recovery Speed Modifier" under the Misc tab, increasing by 5% after every mine detonated. However it seems to be adding some sort of flat cooldown after the first mine resulting in a loss of cooldown with Mixed Munitions allocated.