All cable boxes are property of Comcast, and all used cable boxes available for sale are unauthorized. One is an HDMI Input, which you can use to host another video source chances are you will never use this port. How do I do it? Enter your account number and phone number. One HDMI Cable can transmit digitally (as an example 4K H Make sure the volume is set high enough to hear it (on LG Audio devices, setting the volume to 15 will suffice). What do I do if I get a "No signal" when hooking up the HD cable box? Can someone confirm? {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/9\/90\/Hook-Up-a-Comcast-Cable-Box-Step-1-Version-2.jpg\/v4-460px-Hook-Up-a-Comcast-Cable-Box-Step-1-Version-2.jpg","bigUrl":"\/images\/thumb\/9\/90\/Hook-Up-a-Comcast-Cable-Box-Step-1-Version-2.jpg\/aid4063717-v4-728px-Hook-Up-a-Comcast-Cable-Box-Step-1-Version-2.jpg","smallWidth":460,"smallHeight":334,"bigWidth":728,"bigHeight":529,"licensing":"
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