Hey pal, your English is excellent! thanks for taking the time to give some feedback.
Some other folks I spoke to agree with you about the voices. The actors will be different in the final product, I recorded them roughly so I could check it worked. And we're going to change the script so that each one is brought in one at a time until they overlap.
I have looked on Construct forums about creating a sound timescale scrubber and haven't quite figured it out yet. I've also been thinking about creating visual effects to show when the track starts and ends, so it's nice to see feedback confirming that that's what I need to look into next.
Thank you so much!