AD9517 SPI with AD9467FMC

I just found on wiki page of AD9467FMC that reference design is using default configuration by using external clock and AD9517 is still accessible via SPI. I checked the C code and everything should work well even in Main file  :

ad9517_setup(XPAR_AXI_SPI_0_BASEADDR, 2);    // Initialize device.

ad9517_power_mode(3, 0);                     // Set channel 3 for normal operation

ad9517_frequency(3, 250000000);              // Set the channel 3 frequency to 250Mhz

ad9517_update();                             // Update registers

is also calling but in actual its not working and i am getting distorted signal of 500kHz and so on. anybody knows what configuration should be change?

I read the data sheet and i want to use internal ad9517 VCO instead of external clk.

according to above code channel 3 means lvpecl is using, can we use LVDS?