im not sure if this is a known issue, but heres how the bug occurs...
i have a dex monk, with 20 str (well, will have, currently 19)
i have full wind and ocean stances
if for some reason, you forget to put str item back on before attempting to go into ocean stance, you will bug out due to not having the prereqs to perform this action, and lose your wisdom bonus to ac, only fix is to log in/log out
just a heads up