iMac to HDMI failure

[DanFlesher]

Previously I was using my 2011 iMac with a Thunderbolt to HDMI adapter to connect my Sony TV as an external monitor. Everything worked perfect. Today I hooked up my new Retina iMac to the Sony TV through the same method (Thunderbolt to HDMI) but every 5-10 seconds the connection resets, the monitors go black, and the screen sizes change temporarily - simply to go back 5-10 seconds later to the previous settings (continuously looping through a "connected / disconnected" routine). It is not the cables or plugs as I checked these out thoroughly between iMacs.

Is there some setting I'm missing which will lock down the settings and prevent the monitors from resetting?

Here are my specs:

iMac Retina 5K
4Ghz i7
32gb Ram
AMD Radeon R9 4096 MB
OSX 10.10

 

[lahabra43]

Same here

I have same problem. My sony 4k tv shows black screen when I connect 5k retina by thunderbolt to htmi.
Air play to apple tv is not working also.
I called apple tech support and they tried to solve this problem for total 3 hours vut no success.

that was couple days ago and they will contact me as soon as they find the answer for this problem.

 

[DanFlesher]

Update

Just off tech support, as well. For anyone experiencing this issue, there is not yet a solution and they informed me it is a software malfunction. It seems like this is a pretty widespread issue and they said this will hopefully be resolved in the next software update.