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Your ISP needs to be powered ON and connected to your LAN.
Your ISP must be equipped with a 7+2 eARC HDMI board
Instructions
Access your ISP’s WebUI in installer mode.
Click on the Settings page:
Under the HDMI settings, select the OSD screen format matching your TV or projector. Put it to off Select “off” if you don’t want to use the OSD.
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