AD9694 do not start convertion

Good morning

I am using the AD9694 and I have problem with the A/D convertion that does not start.

The input clok is 500 MHz and the analog input signal is 10MHz 800mVpp (AC coupled).

If I set the A/D in test mode forcing a ramp generation (writing the register 0x0550 0x0f) all is working correctly.

Which could be the cause that put the A/D not converting (all 4 channels) ?

Following my startup initialization: 

0x12 0x28 0x4F
0x12 0x28 0x0F
0x12 0x22 0x04
0x12 0x22 0x00
0x12 0x62 0x08
0x12 0x62 0x00

0x00 0x02 0x11

# quick configuration (Lines = 2, Converters (M) = 2, Octets x frame (F) = 2) b"01-001-001"
0x05 0x70 0x49

# N', N, CS
0x05 0x8F 0x0F
0x05 0x90 0x2F

#disable scrambling

0x05 0x8B 0x00

#enable DCS

0x01 0x1c 0x0A

#set line rate 5GBps

0x05 0x6E 0x10

# Normal Mode
0x00 0x02 0x00

Someone can help me how and what I have to investigate ?

Best Regards

MaurizioB