Drifting is not hard to do, and it always takes various forms. One place we drift is in our responses to God in the worship.
One of these responses is the invitation we have to sing to Him. Our singing is called to be rich, meaningful, overflowing. If the acoustics in this place fight you, then the exhortation is to fight back. If, because of poor acoustics, we must sing twice as vigorously in order to maintain what we have enjoyed elsewhere, it is hardly a good idea to give up and sing half as vigorously. To do so is to slander the psalms of God. If the psalm or hymn is unfamiliar to you, then this becomes an opportunity to listen and read carefully, so that you will have the future opportunity to sing to Him with greater depth and richness.
Another response is the chance we have to say amen. One of the most wretched things on earth is a muffled or muttered amen. While the word says Aye, so be it! our tone of voice must not say I guess or why not. The church father Jerome wrote that the early Christians used to say amen in such a way as to frighten the visitors. After the first few amens in every service, we ought to hear the clatter of some poor visitors’ folding chair.
Of course, in the congregational prayer, the men who are praying should conclude their prayers in such a way as to let the rest of know when to add our assent to what has been said. When we conclude a psalm or hymn, we are called to show that we know what we have sung. The point is not to yell, but the amen should be robust and full of life. We are after all, offering what we do up to God.