No sound from SPK_P and SPK_N in UMTS&LTE EVB

Hello, I’m working with EG91 Evaluation Board trying to take a look into the CODEC IC to connect to a speaker and playing with the AT command for testing.
My goal is to connect SPK output to a bigger, already working, amplifier circuit for hallway voice.

I have had no results trying to make sound come out of the Loudspeaker Interface (J603) in the EVB.

I connected an osciloscope with 2 probes to each pin of J603 (SPK_P and SPK_N) and a reference to GND for each probe, afterwards I tried a few commands to make sound come out:
-Select ACL5616 CODEC IC
-Select speaker mode
-Create a tone to sound over the speaker

With this method the sound comes out only from the J601 headphone jack, I’ve tried all 3 modes for the “AT+QAUDMOD=” but the result is the same.

I have the following documents that helped me try this:
-ALC5616 Datasheet from Realtek
-NCP2823 Datasheet from ONsemi

In the vecinity of the amplifier U801 (NCP2823) there is a connection J604 that maybe is the power source of the amplifier, I’m not sure and I can’t find anywhere what this connection is for.

Is there some step that I’m not taking?
Or maybe something I’m missing in hardware?
I don’t want to try things without certenty, EVB is very expensive and I have olny one.

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I was looking for the schematic of the EVB and found it in this very forum.

According to the schematic, J604 connector is to short VP of NCP2823 amplifier to VBAT

So I tried it, and the NCP2823 started to raise its temperature very rapidly, I’m not familiar with this IC so I kind of got scare a bit and stopped the test.

Even with this connector shorted, no sound came out from the SPK_P and SPK_N pins.