Hello
Yes in V6 you can do it. I'll try to explain :
If you zoom on the soundtrack with TAB, and put your mouse over the soundtrack, you'll see a + on the right side.
Click on the + and then click
- once at the place you want to begin fading : you'll see a couple of two yellow square
- once, let's say at one centimeter right of the first yellow square
- once, at the place you want to end fading
- once, one centimeter left of the last yellow square
Click + again to release
Then drag the second and third upper yellow square toward the middle (sound level 0) so do define fade level and time from high level to fade and then from fade to high