I don’t know anything that solves this because djay does not have the following:
- Beat grids editable in multiple places (see related topic: Edit beat grid at multiple places)
- Being able to tell djay that a track has a static BPM
I have multiple songs that exhibit the behavior you describe and I stopped trying to make it work because the features above are missing. One user once commented that it might be possible to rectify a beat grid by using the “Tap” functionality but this didn’t work as desired for me.