Xduoo X20's voice output is not working properly

[obake]

I'm using the Xduoo X20 with the voice interface enabled.
Right after I boot Rockbox, I get voice feedback of my key inputs for a few times (usually roughly about 10 times).
After that, there will be no voice feedback with no symptom.
No key beep will be output either.
Audio playback is always working fine.
I am also using Xduoo X3 II with the voice interface enabled, and this problem does not occur.
I have tried with Version: 5312fe6bda-210919 and Version: 10f05b3b27-201129.

[speachy]

The x3ii and x20 differ only in the physical controls and the mixer control.   So I'd expect both the X3ii and X20 to otherwise behave similarly.

...I don't have access to an X20 though, so I'm unable to reproduce anything on this end.

[obake]

I looked at and analyzed the situation.
To sum up, the problem has not been solved.
This may not be a voice output specific problem.
Rockbox for X20 seems to crash if there is no sound output for a certain period of time (maybe 10 seconds).
Rockbox for X20 makes an electromagnetic relay on/off sound when starting sound output and shutting down.
This sound does not occur with standard firmware.
Please tell me a way to get debug logs for this issue if possible.
The X20 is the only Rockbox supported hardware with balanced output!
I would like to use it for daily use somehow.

I'm using the Xduoo X20 with the voice interface enabled.
Right after I boot Rockbox, I get voice feedback of my key inputs for a few times (usually roughly about 10 times).
After that, there will be no voice feedback with no symptom.
No key beep will be output either.
Audio playback is always working fine.
I am also using Xduoo X3 II with the voice interface enabled, and this problem does not occur.
I have tried with Version: 5312fe6bda-210919 and Version: 10f05b3b27-201129.