Some times I do and some times I don't, but the point is that is to be done in silent........
There is nowhere in the Word of God that allows the speaking in tongues to be done aloud in front of others when no interpreter is interpreting. If you are doing that then you are doing it wrongly and thus can not come from the Holy Spirit, because the Holy Spirit will not have His gifts done contradictory to what the Word of God says...
Praying in tongues privately doesn't mean silent. I will sing in tongues. I will pray in tongues, and I do it quietly in a whisper often when in church or at home among other people. It is private.
.
.