Sometimes, switching to the Mortar Launcher while having your minigun spun up will cause the movement penalty from the minigun to apply to your movement while using the mortar. This continues until you switch back to your minigun, which will start firing and continue until your press your mouse button again.
I have done this multiple times, its rather annoying. I can't reliable reproduce the bug tho. The second part is when you switch while holding secondary fire, it will not wind up until you unpress and repress the button somtimes.
