Upsampling frequency adjustment in MHZS 88F player

I received the MHZS 88F CD player yesterday. The user manual is in Chinese, and I don't know how to change/select upsampling frequency. I tried to do it from remote but nothing seemed to happen. I will appreciate all recommendations.
Hi Transl
I recall the button to change upsampling on the top row of the remote marked 'kmz'sic. It had to be set before starting the cd.I used the highest sampling as it sounded best to me that way.It couldn't be changed while the player was playing a disc.
Since my 66e had no standby mode,I never turned it off. It took a day to get it to sound it's best when I turned it off.It only had two 12AX7's in my model,which,I was told would last for years even if I left it on.
Enjoy the music
Thank you!
One more thing. You didn't mention if the player is new or not. If it is new, play it continuously for at least a week or more before you start to listen seriously to it. If you like it now it will sound better once broken in.

There is a write up and comparison of the MHZS and some other digital sources that may interest you plus some mod ideas towards the end of the article.

Enjoy the music
Hi Transl, did you ever contact Joe at Pac Valve? Don't know if he will send you an Eng manual or not. Not much to it really, tube rolling is straightforward. As mentioned, you can't change the upsampling while the disc is playing. Push the button while stopped and you should see the display cycle through the different bit rates.
Thanks yo all!

Montejay: Yes, it is new and I think I like it better than my old Cary 308 due to more realistic and uncolored sound. It reminds me of a Blue Note Coala CD player in terms of its great dynamics and midrange liquidity. I connected the VH Audio AirSine power cord and it seems to work nice with this player.

Tholt: I contacted Joe at Pac Valve and he answered "upsampling is done exactly as stated in the user manual". Perhaps, he will answer my question about the user manual in English. I explore the tube rolling options later; meanwhile, I am ordering some NOS 12AX7 tubes.
P.S. No answer at all - he is reluctant to help, though I offered to buy the manual.