Ashira Susanowa

So I've recently been experiencing a rather curious 'bug', quite often when I log in to Second Life, I find one of my prim attachments appears to have been dropped, even though it is still attached, detaching doesn't do anything as the item still appears to be floating where it was 'dropped'. I can't take or delete it in that case either as it is still considered to be attached to my avatar. Usually relogging helps, but when I tried it this time the same thing happened, with a different attachment appearing to be dropped. Any particular reason this might be happening? and does anyone have any suggestions in attempting to correct it? I use the official SL Viewer if that helps.