Timestretch incorrect play cursor ( sample editor )

When setting a sample to timestretch 512 lines ( textured ) , the playhead cursor in the waveform is totally inacurate
Just hold a note and look at the waveform and notice how it stops
I maximized some parts of the waveform so you will hear the difference easily , yet the cursor never reaches that part
innacurate.xrns (16.4 KB)

Reported this, too:

I also noticed that the problem mostly occurs when trimming or cutting a portion of a sample ( when texture timestretch is enabled )
Renoise miscalculates the actual length