Fair enough

Here is my position: Paul stresses that the tongues were not understood without interpretation. This was the opposite of the gift in Acts where the miracle was that people who would not normally understand the speaker could.
1Co 14:1 Pursue love, and earnestly desire the spiritual gifts, especially that you may prophesy.
1Co 14:2 For one who speaks in a tongue speaks not to men but to God; for no one understands him, but he utters mysteries in the Spirit.
A. In Acts they were clearly speaking to men.
B. It says that no one understands them here. In Acts all understood them.
C. They did not simply utter mysteries but were intelligible in Acts.
1Co 14:3 On the other hand, the one who prophesies speaks to people for their upbuilding and encouragement and consolation.
1Co 14:4 The one who speaks in a tongue builds up himself, but the one who prophesies builds up the church.
A. tongues are contrasted with prophecy which builds up
B. Tongues speak to PEOPLE
C. The tongue speaker edifies himself. Clearly in Acts 2 they edified those listening.
1Co 14:5 Now I want you all to speak in tongues, but even more to prophesy. The one who prophesies is greater than the one who speaks in tongues, unless someone interprets, so that the church may be built up.
A. This notes that those speaking in tongues need an interpreter. The whole miracle of Acts 2 was that no one needed an interpreter.
B. Prophesy is therefore seen as more important, building up the whole church through a word from God.
1Co 14:6 Now, brothers, if I come to you speaking in tongues, how will I benefit you unless I bring you some revelation or knowledge or prophecy or teaching?
1Co 14:7 If even lifeless instruments, such as the flute or the harp, do not give distinct notes, how will anyone know what is played?
1Co 14:8 And if the bugle gives an indistinct sound, who will get ready for battle?
1Co 14:9 So with yourselves, if with your tongue you utter speech that is not intelligible, how will anyone know what is said? For you will be speaking into the air.
A. tongues in themselves don't benefit listeners. They must have intelligible content.
B. He compares it to instruments which do not sound a note that is clearly distinguished, so no one knows what is being played. In the same way no one knew what was being said by those speaking in tongues.
C. The trumpet or bugle call in the Bible was for signaling. But tongues was being used in a way that was not intelligible to others.
D. They were "speaking into the air" not to other people.
1Co 14:10 There are doubtless many different languages in the world, and none is without meaning,
1Co 14:11 but if I do not know the meaning of the language, I will be a foreigner to the speaker and the speaker a foreigner to me.
1Co 14:12 So with yourselves, since you are eager for manifestations of the Spirit, strive to excel in building up the church.
1Co 14:13 Therefore, one who speaks in a tongue should pray for the power to interpret.
A. Those speaking in tongues do speak in a language, but one that is not known to those listening.
B. Paul says they should desire those gifts which build others up, not just themselves. So if they speak in a tongue they should pray for the power to interpret. This was not needed in Acts. All understood in their own language.
1Co 14:14 For if I pray in a tongue, my spirit prays but my mind is unfruitful.
1Co 14:15 What am I to do? I will pray with my spirit, but I will pray with my mind also; I will sing praise with my spirit, but I will sing with my mind also.
1Co 14:16 Otherwise, if you give thanks with your spirit, how can anyone in the position of an outsider say "Amen" to your thanksgiving when he does not know what you are saying?
A. Both speaking in tongues and speaking with the mind are necessary.
B. the audience could not say amen (truly, etc.) because they did not know what was said.
1Co 14:17 For you may be giving thanks well enough, but the other person is not being built up.
1Co 14:18 I thank God that I speak in tongues more than all of you.
1Co 14:19 Nevertheless, in church I would rather speak five words with my mind in order to instruct others, than ten thousand words in a tongue.
A. In tongues we give thanks but others are not built up
B. five intelligible words are better than ten thousand words in a tongue because they are not known.