I am a bit confused. By "constant tempo" are you using that term to be a synonym for "tempo map"? Cause, mixing audio tracks which have a slightly different tempo would involve some degree of pitch shifting. On the other hand, using a tempo map will permit you to mix audio, which is not consistently played to the grid, with midi.

Reapear will create a tempo map, Melodyn will create a tempo map and SMP will also do it. All three with the push of a button. I used all on a recent project and they all worked great.

Or am I just showing my ignorance.

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