Start the OSC application as root and you will see the advanced tab.
http://wiki.analog.com/resources/tools-software/linux-software/fmcomms2_advanced_plugin
After you found the optimal settings you can update your device tree with the new defaults.
http://wiki.analog.com/resources/tools-software/linux-drivers/iio-transceiver/ad9361-customization
Greetings,
