Helm Anton

Im an animation creator, recently i have moved to making combat animations for people. A problem im seeing is that the hands which are set to fists will open up into palms after about 30 seconds time. They are set to Pri 4 which is as high as i can go through upload. I know theres highier priorities though, i just cant set them. Whats going on here? why are or what is over riding the fists animation? I was told by another animation creator to try and set the fade in and out to .5 and see if that helps , as they think its the T pose in the animation programme is causing the hands to relax, but if so why?...the animations are set to start at frame 2 not 1 which is were the T pose is.