Randomly while playing a random level as this has no effect on which level, my trinket in the middle slot will become unusable for some reason, I don't know how to replicate as this happens randomly, this does not occur from a death, or from falling off the map for a reset, however death will clear the issue until the trinket is used again.  it shows as grayed out like it is in use, and you can not swap to another trinket because its counted as on cooldown.  leaving level and re-entering will clear problem, until it happens again.  Close game and reloading game seems to reduce how often this happens.