TAS2563: Possible malfunction of Tone Gen (0x3F) and Tone Gen mixer coefficients

Part Number: TAS2563

Tool/software:

Hi, some engineers.

I'm currently asking this question in another thread, but a new question has come up so I'll ask it here.

I was experimenting with various elements in the PPC3, and when I wrote firmware to the mounting board with a certain setting, I confirmed that the speaker was outputting low-frequency vibrations immediately after starting up.
When I measured the Class-D output, I found a peak at 60Hz, which immediately led me to suspect the operation of the Tone Gen.

But when I checked Addr: 0x3F, the value was 0x00.

The above phenomenon is currently occurring.

I also suspected that the sample rate was incorrect, but I don't think that's the problem because the I2S audio is output normally from the SPK.
(The audio is superimposed on a 60Hz vibration.)

I also suspected hum noise, but since the power supply fluctuations around the TAS2563 are minimal and the 60Hz output from the SPK is about 7dBV, I think this is unlikely.

There may be other registers related to Tone Gen that are related to this issue, so I would like to know what those are.
I would also like to know what registers are related to Tone Gen's mixer coefficients.

Regards,

Fumiya.