Question about the DNSMOS on clean speech

[SaoYear]

Hi,

I have a question about the updated version of DNSMOS.835. I testified the clean speech performances on the DNSMOS (non-personalized), but found the model would give a score only about 3.2-3.3 for even clean speech.

Implementation:
I directly used the dnsmos_local.py and the .onxx files provided in this repo.

Here are some results (all clean speech):

1. LibriTTS (~25k wav files): 3.23
2. DNS-challengeI test set, synthetic clips without reverb: 3.28
3. CHIME4 simulated test set: 3.31

It seems that the upper bound of the current version of DNSMOS is about 3.3.
My question is that, is this the intention of the MOS score?

Many thanks in advance!

[hollandloprabbit]

I have the same problem, any explanation?