Translation analysis: While not affecting the meaning, the KJV appears to be missing the image of a threshold (or rather is subsuming it into the "posts of the door").
Gileadi (p. 107)has:
The threshold shook to its foundation at the sound of those who called and a mist filled the temple.
The NIV has:
At the sound of their voices the doorposts and thresholds shook and the temple was filled with smoke.
Scriptural analysis: In any case, the image is of voices of such power that they resonate through the building, and shake it. The building in this case is the temple, and the temple is filled with the presence of God. In verse 1 we have specifically his robe. Now the temple is filled with smoke (or mist, in Gileadi). There are two possible explanations of the smoke. One would be the symbolic smoke from sacrifices. That smoke is the offering to God, and is in place inside the temple. God is there as is the sacred smoke of the offerings (and offering of obedience) to him.
Another possibility is to relate the smoke to the live coal mentioned in verse 6. However, as the live coal comes from the altar, it is quite likely that we are dealing with a sacrifice where the smoke is present, and the burning of the sacrifice produces the live coal.