Exactly how I wrote on the title. Iron Halo doesn't activate while sprinting anymore. I used to pop it up when I was running towards the enemy but now I noticed that I have to stop first to be able to activate it. I suspect this was not intended(and probably happened when you made it available to activate during knockbacks in the last patch) because it's not fun at all and it takes a lot of usefulness from the ability. My muscle memory is so used to it that i'm having trouble adjusting to this at the moment even though Heavy Class has always been my main class.