Scenario 1:
Primary class Invoker, Way of Kaeula
Secondary class Engineer, Impact Turret
Scenario 2:
Primary class Engineer, Impact Turret
Secondary class Invoker, Way of Kaeula
Amulet Hyperconductor
If the Invoker skill has more than 1 charge, activating Impact Turret (in either turret or carry mode) consumes all charges and puts the skill on cooldown. Also tested with Invader, Wormhole (2 charges) and did not experience the bug. Vulcan and Flamethower did not exhibit this interaction. Scenario 2 did not trigger the bug when the Invoker skill only had 1 charge (without Hyperconductor). I haven't unlocked other Invoker skills yet so I can only test Way of Kaeula.
I can include the rest of my build setup if it seems relevant.
Edit: this seems to be unrelated (happens without Invoker), but I just noticed that Impact Turret only summons in with half ammo. Is this intended?