diff --git a/requirements.txt b/requirements.txt
index 4b162b15..8b532c0b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -63,7 +63,7 @@ lxml==4.5.1
 Markdown==3.2.1
 MarkupSafe==1.1.1
 matplotlib==3.2.1
-mkl-fft==1.1.0
+mkl-fft==1.0.6
 mkl-random==1.1.1
 mkl-service==2.3.0
 mock==4.0.2