Hi Matt,
I had used a 4K Player connect to the input port HDMI A of the ADV7526 Demo Board,and the output port TXA of the Board connect to the SONY TV(TV support 4K) .Now send a command "Route a txb" by RS232 to set the Board working Mode is Splitter.Wait the Video is output normal,and then send command "Route c txa" to change the input source of the output port TXA,and then send command "Route a txa",you will see the TV appear a un-normal signal,full screen white point.About 2 seconds then output signal change normal.10 times may be appear 8 times.