I had a lot of trouble with this chord so now I Bar the the first two strings like in the full bar F chord and I don't get muted strings.Another way I have success with it is to fret the E and B strings normally with my index Finger and the A and F notes with my 3rd and 4th fingers instead of my second finger [M] which is the problem Finger for me.Either way I don't get muted strings.