Game Mechanics: capped at 14 instead of 15 active buffs/debuffs

[spoil]

The only 'solution' I've found is if I nuke myself down to where my buffs disappear on zoning, my character returns to normal for a while -- my buffs act normally, they don't swap places when I zone and I can get up to 15.

Unfortunately that's not a permanent solution and not realistic to do this every time my character is bugged. Not sure if that's useful to solving the issue.