Both pronounciations are right!
There are two alternative pronounciations for the word-T can pronounce or not
I've done it both ways. The problem is they both sound right to me, so I'm not sure which I would use naturally in a sentence.
i don"t think that emphasis here is on the pronounciation of the 'T' or not...but on the auxiliary 'do' because often can be pronouced with the 'T' or without it....yet, the sentence n°1 is correct with or wihout "do" because the use of "do" = insisting on ofTen
it's BIT tricky