DJM 900 NXS 2 Digital Out Problem (Used oppo 203 universal blu-ray player)

Hi.

I am currently testing a unusual system.
I have to connect the DJM 900NXS2 to the hifi system and adjust the sound of various sources in real time.

I connected two OPPO 203 Blu-ray universal players and my PC to the mixer with SPDIF RCA. And DAC is using 818V3 of MERIDIAN of UK. This is also connected to SPDIF RCA.

But there was a problem. I play the CD or Blu-ray disc and change to the next track during playback, there is a problem that DAC does not recognize the sample rate and no sound.

I have fixed the oppo sound settings to lpcm 48 or 96khz. djm 900 nsx2 is fixed at 96 kHz. If I do not hear the sound, I will take the sound out by converting the digital master output sample rate setting of djm 900nxs2. When I change the setting of djm 900nxs2, no matter what sample rate I set, the sound will play again.

Connecting oppo and meridian directly does not cause any problems.

I think it would be solved a problem if djm send the information about the current input signal back to the DAC when the sound is stopped and running again. It is generally known that hi-fi systems use this method. 

This was not the case when I used analog input and digital master output. I have not been able to test this method for a long time, so I'm going to do some more testing.

I purchased a DJM mixer that I could use to digital input spdif to get better music playback.If you have a solution, please let me know.

And one more question, is there a way to turn off the setting lock?
If I go back to the main after setting, lock will be set automatically.

I will wait for an answer.