Weird sound in Mbox 2 & Mbox Micro

[linderefter]

Ok,

I'm working with PT LE 8.0.5

At first, I was listening something weird with my mix (with headphones and monitors). Like if it was out of phase.

Then I realized that if I wanted to "hard pan" one track, I was still able to listen some signal in the opposite side.

Then I listened the click track only (just a mono track, no insterts or sends) and I heard an "after sound" something behind an after the click... Like a shadow.

And that's why my whole mix sounded weird.

If I open the same session with my 003 or HD system the problem goes away, but sometime I work with my Mbox's.

I've tried:

Different buffer size, output reset, internal sound in system prefs, etc.

Please Heeeeelp!!!