This is now happening on my electric/electric Brute. I was level 16 and doing so well on endurance that I was joking with my wife that I could push Stamina back because this guy was using next to no endurance at all. My missions were on Malicious and I was breezing through them. Then I put him away for a week or so to work on some other characters.
I came back to him a few days ago and soloed the Skyway mayhem. On Malicious, ended up with 28 minutes at one point. Did a couple side-missions, and basically breezed through the whole thing without issue. Got my debt protection self-rez and moved on to other missions.
Then I started noticing that my endurance was dropping very quickly. I was spending most of my time resting, fighting maybe one group then resting again. I ended up putting my missions back to Villainous because my blue bar couldn't handle Malicious any more.
I thought maybe because my DO end reducers (in all my attacks and toggles) were yellow that might have been the problem. So when I hit 17 I bought 20s to go in there. Didn't affect the problem one bit it seems.
I was even in a group with other brutes later that night and noticed that you could tell which were brutes easily enough because if you looked at the party status bar the brutes were the ones with no blue bars. There were four brutes in this group and we took turns between resting. The process was basically fight a group with endurance, fight a group with no toggles running and only the low-endurance attacks, then rest. Rinse and repeat. We each did this, so basically out of four brutes I would say we had one-and-a-half active each group of mobs. That's horrible.
