[To me, I'm clothed. To the REST of SL, I'm bucknaked.]

I have had a similar problem but in reverse - my partner and I are having 'adult' time, and one or the other of us will inquire as to why the other is still dressed.  Usually doing appearance will fix the problem, although I have set up a 'clear visual cache' tool on our island, and use it reguarlly.

 

Don't know if that will help.