!!! I found an interesting solution:
I installed the program in portable version and everything works smooth now. !!!
I used to be able to use Reaper with no problems. But one day, I started to get a very distorted sound when I'm playing my recordings on Reaper.
Fact 1: Reaper renders my projects as its supposed to be (not distorted)
Fact 2: I can use Audacity with no problem
Fact 3: I can use EZmix (which I also use with ASIO drivers) with no problem.
*I tried to play with buffer size, but It didn't affect anything.
Do you have any idea? I can upload the screenshots of the Audio-Device-Setup settings if needed.
Sound samples (simple clean chord recorded as dry guitar sound):
Screenshots of the settings:
4. Audio Device
Thank you very much for all your help,