HDMI input (computer) often fails to receive audio or both audio and video
Using a brand new TCL Roku TV (4 series) as main 4k computer monitor. This is replacing a Samsung that was used in same place/setup for 10 years on 2 different mac Minis). Sometimes it works as it should, but frequently when powered up, it won't see video or audio from the HDMI input, and sometimes it will see image, but get no sound. Have tried ALL 3 HDMI ports, used different cables, including a new one I just bought (certified as 4k capable), and the issue always comes back (sometimes). Right now, at wake, it saw video, but no audio. Powered off the TV, tried again, same issue. I'm an AV tech by trade, so I've tried the basics, it's no a cabling, signal path, or input issue. It's gotta be some sync issue with the computer and the TV.
Re: HDMI input (computer) often fails to receive audio or both audio and video
I use my Sharp Roku TV as my secondary monitor while teleworking. On occasion it has lost its HDMI connection between the docking station and the TV, and I have to unplug the HDMI cable and put it back in. It's simply lost its HDMI handshake. Fortunately, it doesn't happen very often. But when mine does it, I get nothing, no audio or video.
When you turn the TV off, it's really only on standby, so it doesn't force an HDMI handshake signal. Pulling the TV power would force that handshake when powered back up.
Personally, I think it's likely something on the computer side. As I said, I am using a docking station, and even though I have screen sleep disabled my guess is the HDMI connection is shutting down on the computer side and not properly asking for a handshake when it resumes.
My work computer is an HP ZBook running a version of Windows 10 that is tightly controlled by our IT department. I don't have admin privileges, so I can't experiment with any device settings.
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