FMCOMMS4 with ku040 not transmitting with abnormal behavior on TX and RX chains

I am evaluating FMCOMMS4 through no-OS build. I am trying to transmit ramp digital data modulated on 2.4GHz carrier. FMCOMMS4 should run in FDD mode with both RX and TX enabled and with LVCMOS IO. I flash the fpga with the test build. I can measure at the first beginning the ramp digital data on the TX lines visible on some test points on FMCOMMS4. When I initialize FMCOMMS4 through SPI, the tx digital data lines got 500mv peak to peak random signal modulated on both high level and low level and no RF TX signal is present on the spectrum analyzer.

I tracked down the code to find what is causing this on the digital tx lines. I found out that whenever I enable the RX-synthesizer, the modulated signal appear and when disabling the rx synthesizer the signal get back normal.

I did another experiment, I swapped P0 and P1 data (basically RX and TX data) and did the test again. A peak at the spectrum analyzer showed at 2.4GHz. The RX digital lines show the ramp signal and the TX digital lines show high amplitude random signal. The signal that is present on TX digital line (TX_D5_P) is attached in the message.

I reperformed the first experiment but i injected a radio frequency signal, single tone, with a frequency 2.405. What i noticed is that no digital data appeared on RX digital lines and I got a 5MHz signal above the random signal i am getting on tx digital data lines. Any clue here to make this work?