To get the highest quality signal from your source to your display when you use an HDMI extender, do the following:
Make sure that the HDMI versions of the source, extender, and destination are compatible. For example, if you require 3D support, make sure that all of the devices can support 3D over HDMI.
Use the least amount of adapters, splitters, or converters as possible. Each device that you use in your setup creates additional points of potential failure and creates more steps for an HDCP key to hop through, which may cause issues with older displays. For more information on HDCP, refer to the following FAQ: http://www.startech.com/faq/video_signal_converters_HDCP.
Use an HDMI extender that exceeds the requirements of the setup. For example, if you need to extend the signal 200 feet, it is best to use an extender capable of more than 200 feet.
Make sure that all of the CAT 5/6 runs are as straight as possible, with the least amount of coiling.
Make sure that all of the patches, wall jacks, and cables use the highest possible CAT specification, (for example, CAT 6), and were tested to conform to the standard.
Use patches, wall jacks, and cables with the same pin configuration. For more information on T568A versus T568B wiring, refer to the following FAQ: http://www.startech.com/faq/network_cables_a_vs_b_pinout.
Keep the cabling away from sources of high noise.
Make sure that you use adequate electrical grounding in your setup.