06-22-2020 09:06 PM
I purchased the LG CX OLED TV two days ago from my local BB. I am replacing the LG C8 OLED. I also own an Onkyo receiver and the UBK-90 LG 4K Blu-ray player. The 4K player is setup with 2 HDMI cables; one for video out and the other for Audio out. The 4K player is set to output all audio through the Audio HDMI output or HDMI 2. The audio HDMI is connected to the Onkyo receiver. The other cable is going to HDMI 1 on the LG CX TV. The Onkyo receiver is connected to HDMI 2 on the TV. This is the Simplink (HDMI-CEC) connection. Auto Device detection is turned off in the TV settings.
This is what is supposed to happen. I turn on the TV. The receiver starts up. I turn on the 4K player. The TV switches to the HDMI that the 4K player is connected to. The receiver switches to the audio HDMI connection the 4K player is connected to. The movie plays and all is right in the world. This is exactly how my LG C8 OLED functions. Every once in a while the connections will get crossed but a simple restart of the devices generally corrects any issues.
This is what is happen with the CX. I turn on the TV. The receiver starts up. I turn on the 4K player. The TV switches to the HDMI that the 4K player is connected to. The receiver switches to the audio HDMI connection the 4K player is connected to. The 4K menu appears on the screen. Almost immediately, the TV switches from HDMI 1, 4K player, to the HMDI 2 (ARC) connection and trys to pull the video from the receiver. The image from the 4K player is instantly corrupted. If the movie starts, then the the audio is exactly as I would expect it.
This is what I have tried:
1) I have tried forcing the input selection from the TV menu to HDMI 1. The TV auto switches back to HDMI 3. There does not seem to be anything I can do stop this.
2) I have connected a fiber optic cable to run between the TV and receiver. Switch audio output to fiber. When I turn on the 4K player the TV selects HDMI 1, 4K player, and then auto switches back to the receiver thus corrupting the video.
3) Turn off Simplink (HDMI-CEC). The audio instantly converts to something not HDMI. The 4K player will start. The movie will play. The audio is non-existent because the 4K player was instructed to output all sound audio to it's Audio only HDMI port. I also have to use the receiver remote to make any adjustments to volume or audio processing.
4) I go into the TVs input menu, Home Screen, and explitcitly select HMDI 1 connection. The TV will momentarily switch and then auto pick the HDMI 3.
5) Hard reboot all equipment. I unplugged everything. Issue persist after restart.
6) Updated software for all components. Issue persists.
What did work:
1) If I unplugged HDMI 2 ARC connection from TV then everything worked without issue. The video plays normal from the HDMI 1 port on TV. Audio plays through the receiver on as expected.
2) Turn off the receiver. Turn off Simplink (HDMI-CEC) on the TV. Turn on the 4K player. The player and TV sync up. Turn on the Receiver. Video plays from TV without issue. Audio plays from Receiver without issue. Control has to be performed from each seperate remote for each piece of equipment.
Is there some special trick to get all these devices to behave as designed? This is looking very much like a software bug in the LG CX TV.
Solved! Go to Solution.
06-23-2020 06:03 PM
I'm still working my own problem. And reported it to LG. I got an answer that I will sum up here:
1) Unplug the TV, press the power button for 15 seconds to discharge all elecricity in system, and then plug the TV into the wall. Test again.
2) Factory reset and try again.
I performed both tasks. Still having issues with TV. This is what I found out:
1) I turned off CEC on the receiver. This means that the TV cannot control the receiver including managing volume or auto switching inputs.
2) I left the receiver set to the TV input
3) I turned on the 4K player. The TV auto switched to the Receiver instead of he 4K player. The TV also renamed the 4K player input to BD Player on the TV input screen.
4) I manually told the TV to switch to HDMI 1; 4K player.
5) The TV Auto switched to HDMI 2 which corrupted my signal. The TV input is still selected on the receiver.
For some reason, the TV is giving more weight to Audio Only HDMI connection on the 4K player than the direct HDMI connection from the 4K player to the TV. I hope LG takes this seriously. Otherwise, I will be returning this TV and replacing it with my older TV. At least the older TV handles these devices as intended.
06-23-2020 08:33 PM
06-24-2020 07:04 AM
Bobberuchi, thank you for your comments. It got me thinking to try another tactic. I was operating under the predicate that to achieve the highest sound and video fidelity I had to use two HDMI cables; one dedicated to video and one dedicated to audio. So, being a man of science, I chose to switch how I attached the problem.
I know that everything will work as expected with a single HDMI cable from the 4K player to the reciever. Then the receiver will pass the video to the TV and the audio will remain with the receiver. I did a little digging for an explanation of why the more expensive 4K players had a dedicated Audio out and what the benefit was. I found this post on the Sound and Vision site.
Bottom line, the seperate outputs are for older receivers that do not align with the current equipment standards. In my case, the equpiment's automation went crazy town because it did not have a clear understanding of my intended purpose for the equipment.
Solution: use a single cable from 4K to Reciever with HDMI 2.0a ports, to TV. There is no need to seperate the audio from the video. 4K/60, 4:4:4, and HDMI 2.0a are all things you can look in your receiver's manual for to help you determine if you will get full fidelity over a single cable.
Hopefully, this information will help another home theater adventurer save time and frustration.