Hi, AudioTrack. Thank you for your help.

I just tried to install BB2018 to my new laptop (Win11).
Did not work!
Lots of error messages like "the installation of such and such file was cancelled" etc.........
I gave up.
I don't think BB2018 works in Win11 computer.

I also tried to install BB2025 to my old laptop (Win10) and this was a success.
Looks like I can use both BB2018 and BB2025 separately, but the C drive is nearly full.
Anyway I made the same song (same chords, tempo, tempo change) and there was that hiss noise.
That means it's not the computer issue.

If it's not the software issue either, and if it's because of the way the drum swirls,
then what RealDrums set should I buy to be able to make a ballad with double time feel???
Please someone tell me!

Regards,
Jazzutako