diff --git a/requirements/audio/audio_tts.txt b/requirements/audio/audio_tts.txt
index 5cff1b28..972bb992 100644
--- a/requirements/audio/audio_tts.txt
+++ b/requirements/audio/audio_tts.txt
@@ -15,7 +15,7 @@ protobuf
 ptflops
 ptyprocess>=0.7.0
 pygments>=2.12.0
-pysptk>=0.1.15,<0.1.19
+#pysptk>=0.1.15,<0.1.19
 pytorch_wavelets
 PyWavelets>=1.0.0
 scikit-learn
@@ -23,6 +23,6 @@ sox
 tensorboardx
 tqdm
 traitlets>=5.3.0
-ttsfrd>=0.1.2
+#ttsfrd>=0.1.2  # not supported for py311 or above
 unidecode
 wcwidth>=0.2.5