[Major B]

I'm a first user on this forum.
I have a problem using Protools M-Powered 7.3.1 and the M-Audio Projectmix I/O.

Some songs that I've made in the past wil play all fine, but some other doesn't?
When I'm using midi (that's the problem I tink) the cursor does not run and some music is beeing played but not all and eventually protools freezes.
Also when I go to Setup and then to Hardware is freezes and can't do nothing but kill ProTools

does anyone have got the same problems too?
Let me know, Maybe I can fix this?