OK, a seeming newbie asks a serious question and he gets flamed by some of you. And from some of his earlier posts, he looks OK to me.
To answer your question, it seems as if you first need to ask yourself why. In effect, why have you (all of a sudden, it seems) started losing muscle mass? Is it, as other posts have asserted, burning the candle at both ends? It sounds as if you think it is being stuck on a strict diet. OK, but why? Is it because you have conflicting goals? It is tough, if not impossible, to add mass without giving up (for a short time, at least) that dry, ripped look you have.
My suggestion would be to change one thing (and only one thing) for two weeks while monitoring your progress. If, for example, you think it is your diet, add Surge or perhaps a serving of Grow! with your post-workout meal. If it is too much cardio, cut back to once a week or so. If there is positive change after two weeks, keep it up; if the change is negative stop.