When I give out ammo packs via quick action button and I switch back to my gun and press the mousebutton to fire, nothing happens. I have to push the button again.
Happens also as Sawbonez, Proxy and Phantom. About the other mercs I dont know, I just play the 4.
Yes, i have that too. I keep encountering that with various Mercs. It seems to happen whenever you switch from a non-weapon to your primary whilst you press you left mouse key or something.
Then you have to wait a few frames before you can fire again.
Which is mostly enough time to die because you switched to the primary weapon for a reason 