Problem with CS4398 in software mode

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Hi,
I'm trying to build my first dac (CS8416, CS8421 + CS4398). The problem is that there is no signal output from CS4398 😕

The CS8416 gets the audio data from computer SPDIF (24 bit, 96 KHz). The output signal from CS8416 will be converted by CS8421 into 24 Bit, left justified, 192 kHz. The both CS8416 and CS4398 are controlled by AVR in I2C mode. I can read and write any internal registers of CS8416 and CS4398 via I2C and display their contents on the LCD connected to the avr.
The CS8421 configured like this: 1,96K at SAIF and MS_SEL , 63,4K at SAOF. The CS8421 has a crystal 24,576 MHz attached.
The CS8421 outputs the right signal as I see it on my oscilloscope. The status pin SRC_UNLOCK is low (goes high when I cut the source off). The CS8421 is connected to CS4398 via resistors 75 Ohm like that: 10 pin of CS8421 ->6 pin of CS4398, 10 pin->3 pin, 13 pin -> 4 pin, 14 pin-> 5 pin of CS4398. All DSD Inputs of CS4398 are connected to the ground.

I've checked the output voltage at the outputs A and B of the CS4398. The strange thing is that the outputs A and B have different levels. AMUTEC - low, OUTA-, OUTA+ around 5V (relative to GND), BMUTEC - around +5V, OUTB-,OUTB+ - around 0 V. The differential voltages (OUTA+/- and OUTB+/-) are zero.

Is that a kind of a noise protection to minimize the channel influence on each other? Have I burnt the chip?

I initialise the CS4398 like that:

0x8:0x40
0x2:0x02
0x3:0x9 0x4:0xC0
0x9,0x10

Have I forgotten something?
Please help..
 
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