They will synch better but there still a bit of drift within the file

You would need Melodyne Editor or whatever to do stuff such as guitars the easier way is pull the drums into Melodyne it will tell you the speed. Then in Reaper set the speed to exactly what Melodyne tells you say 105Drums and set the Bpm tp 104.862. Then pull the file into Reaper. Change the speed to 105 Bpm and render. Then create a new project for Drums105 set the project speed tp 105.046. Do the same change the speed to 105 then pull the previously rendered file in and they should synch.

Tony.

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