If your entertainment system is using passive HDMI® cables longer than 5 meters (16’), odds are you will have sparkles in your television picture. These long HDMI cable runs can cause disruption in the High Speed Data1 (*TMDS) causing the “Eye” pattern to collapse, which in turn causes sparkles in your picture.

Depending on the specs of your system, Metra Home Theater Group offers three options that will rebuild the “Eye” pattern and get rid of the sparkles:

• If you have a 1080P TV and your cables are distances of up to 30 meters (100’), use the HDM-SR1A in line at the display. This product has low speed data accelerators built in to keep the Eye Pattern intact.
• For 3D televisions and cable distances up to 30 meters (100’), use our HDM-SR1HS in line at the display to fix the eye pattern and get rid of sparkles.
• Our HDM-GA1 has built-in DDC Correction Circuitry and repairs EDID rise time while working in both directions. This product works to support 4K/60, 4:4:4 and/or HDR up to 17 meter (60’) cable runs and is installed at the display.

These products solve the most common reasons sparkles may occur. If these do not solve the sparkle issue, something more complicated may be the cause. Call our technical support team at 1-866-839-9187 and we will be happy to assist you in diagnosing the problem.

*Transition-minimized differential signaling (TMDS), a technology for transmitting high-speed serial data, is used by the DVI and HDMI video interfaces, as well as by other digital communication interfaces.
Source: Wikipedia — Transition Minimized Differential Signaling (article)