The problem is the package named Rubberband installed on my openSUSE
Tumbleweed has version 1.8.2. But it's developer already has released 2.0.2
version of this package. Rubberband is working with EasyEffects program to
make lower the pitch to A432 Hz on my computer. But it's out to date now. I
think that this circumstance may somehow affect the quality of the EasyEffects
program. In any case, a newer version of the Rubberband package is highly
preferred. 
If you interested, here is
the topic of discussion about EasyEffects I was created earlier:

https://github.com/wwmm/easyeffects/issues/723

The developer of this program has already taken into account my wishes for
its improvement and will soon release an update. But for now, the version
of the Rubberband package that is present on my system is outdated. I
really wish the Rubberband was newer.