How do I stop my MacBook switching my TV monitor off?

[Jordus II]

Hope you can help me.

When I connect my MacBook (2015 running Os X Capitan) to my TV (Panasonic Viera CX-400) using HDMI it displays the screen as it has always done but then the TV shuts itself down after 20-40 seconds. It doesn't just go blank or anything it shuts itself down.

It has worked fine over the last week since I got the TV (It's new), I haven't changed any settings on either device (That I'm aware of) and other HDMI inputs such as XBOX and normal TV are working fine.

Any ideas of what could be happening?
(I have tried restarts, have unplugged the TV, used different HDMI slots)

/J

 

[Dwayne82]

Some possible solutions:

- Try to turn off the HDMI-CEC (Consumer Electronics Control) on the TV. Panasonic uses the branded name VIERA Link (or HDAVI Control, EZ-Sync). Albeit Apple MacBooks don't support this protocol, it could happen that the TV interprets some "signals" the wrong way.
- Use an other HDMI-cable (for resolutions higher than 1080p, be sure to use at least a HDMI 1.4 cable)
- I Assume, the rMB uses it's native resolution (2304x1440) to feed a 4K panel. In OS X settings, set the resolution of the external monitor to 1080p (1920x1080) to exclude some conflicts. (an XBOX for example sends also 1080/60/50p signals).
- If the 1080p Resolution works, try to send the native resolution of the TVs panel (4K = 3840x2160 60/50/30/25/24p, the rMB only supports 30/25/24p). If this works, you can also try "3K"50/60p (2880x1620) or "1.5K" (2560x1440).
I Don't know, if all the resolutions for the external screen are available in the OS X system settings. But a 3rd party app like SwitchResX should do the trick.
- Use an other USB-C to HDMI adapter.

Hope, one of the suggestions helps, let us know.