Hi, slowing down using F5 and a negative % works but I found on playback in BIAB it sometimes stops for short periods in playback. It is fine once rendered. I also found it a bit complicated but ok once used to it.

At the risk of sounding like an advertising guy my preferred method is to pull the files into Reaper. Set the playrate option to change playrate whilst holding key then add an automation lane to alter playrate. Then simply drag the rate and slope shape to what you want. Very simple and extremely efficient.

My thoughts

Tony

HP i7-4770 16GB 1TB SSD, Win 10 Home,
Focusrite 2i2 3rd Gen, Launchkey 61, Maton CW80, Telecaster, Ovation Elite TX, Yamaha Pacifica 612
BB 2022(912) RB 2022(2), CakeWalk, Reaper 6, Audacity, Melodyne 5 Editor, Izotope Music Production Suite 4.1