To reset it I have to power down the TV, unplug AC, HDMI cables and wait about 15 minutes. Apply power and the HDMI cable and it usually clears up until it happens again. To me this is a design fault. To its makers it's a security feature.
You may have to remove this from the HDMI switch box.
Bob
I recently purchased a Samsung AllShare Cast Hub so that I could mirror my Galaxy S3 phone on my Vizio E600i-B3 TV. I hooked up the AllShare Hub through my Vizio S5451w-C2 soundbar. Everything worked great! Later, because I have to share the two soundbar HDMI inputs with my cable box and my Blu-Ray player, I installed a Monoprice 4X1 HDMI Switcher between the soundbar and the AllShare Cast Hub (the Blu-Ray player is also connected to the switcher. Again, everything worked exactly as expected. I could switch flawlessly between mirroring my Galaxy S3 and watching a Blu-Ray. Both audio and video worked perfectly. Today when I switched on the AllShare Hub and tried to mirror my phone, only the video worked. No sound! The Blu-Ray audio/video worked fine when I switched the inputs on the Monoprice switcher. I've since removed the Monoprice switcher and individually connected the Blu-Ray player and the AllShare hub. Still, no audio from the AllShare hub, but the Blu-Ray player works fine. I've confirmed that all inputs/outputs are setup correctly. I've since found several web discussions regarding intermittent audio from the AllShare hub, but found no resolution. Any suggestions would be greatly appreciated!

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