I repeatedly watched episode 1 to confirm if it really is the original Naksu's voice inside MuDeok's head.

IT IS!!!!  

if that's the case, they sound so similar!!!

Honestly, they sound too similar for you to be this sure. JSM are claiming its her voice and GYJ's fans are also claiming its her. So who knows

You will notice the distinction if you listen closely. Try listening to GYJ's voice when she's still acting as Naksu, then listen to MuDeok's thinking voice when she was still acting blind and riding the boat (still GYJ's voice), right before JSM speaks.

I also thought it's yoon jung's voice. But in the last episode I thought it's So Min's. I don't know I'm confused.

I agree that it is GYJ voice but as you can see, they are so similar that most people cannot tell them apart so it honestly doesn’t matter that it’s her voice since nobody can recognize the difference.  

 AncientLoveGoddess:

I agree that it is GYJ voice but as you can see, they are so similar that most people cannot tell them apart so it honestly doesn’t matter that it’s her voice since nobody can recognize the difference.  

yeah you're right. 

It’s GYJ’s voice. It’s good that people can’t distinguish them, because when it come to her finally returning, people will hear similarities & have a sense of nostalgia. 

It is Yoon Jung's voice because she is  given credits at the end when her voice is used. 

Guys, don't fight. If you watch GYJ's work you'll realize that her voice simply is very similar to JSM's. That's why it's so hard to distinguish them. It's just a curious coincidence. But it did make showrunners weak attempt of keeping og Naksu at the back of our minds rather futile.

yes most of mudeok inner voice is gyj's  but early ep i remember i heard jsm's
for example when shes under the blanket in janguk's room. thats clearly jsm's


 Tok Mun Shi:

I repeatedly watched episode 1 to confirm if it really is the original Naksu's voice inside MuDeok's head.

IT IS!!!!  

Not all, some is and sometimes it’s actually JSM.

After using my headphone for the voice over - it is 100% GYJ's voice.

When I get a chance I’ll rewatch and tell you exactly the parts that wasn’t GYJ’s voice. She did some but not all. I will definitely get back to you on this.

 Sokha Sen:

After using my headphone for the voice over - it is 100% GYJ's voice.

Episode 1.- 29:18 when Mudeok was given chicken to eat by the man that was selling her and she said in her head about not eating chicken. That was So min’s voice,At 30:20 again thinking voice at the brothel when the man was leaving her there that was So mins voice( thinking voice)

Listen closely to so min talking voice when she first speaks to Maidservant Kim, she then is seen outside thinking whilst walking it’s the same voice  100%.

When she imagined doing the spell on Uk in the bathhouse ( the tornado spell) and Uk caught her smiling ( that was GYj, not just because she actually did that scene) but so min and GYj have different undertones, So-Min did an amazing job of trying to get her tone to match but if you listen closely to both actresses you can hear the difference in their undertones . If you listen without thinking about who is talking ( without looking) you can hear the difference the the tones from both actresses 

In episode 10 for example all the thinking voice as far as I remember is GYJ ( listen for example at 1:11:37 when Uk was telling her about the love letter and she thought( I should’ve braced myself before letting someone get this close) you can hear  a very clear difference in Mudeok’s actual speaking voice to thinking voice. Do the same with episode 1 and notice that Mudeok’s (so-Min’s) actual voice carries a specific undertone that matches with her thinking voice in some scenes. It’s also best not to listen with headphones, listen without looking at the screen. It tends to be clearer then And stat at The very first scene of Naksu introducing herself ( listen for her undertones)?