HDMI CEC and black level issues with new Shield

by rickdmer

I just got a new Shield today and I'm having some issues with it.

Firstly, the HDMI CEC volume controls don't work. I am able to control the UI with my TV remote, but the volume buttons on the controller do nothing when the system volume controlls are set to HDMI CEC mode.

Secondly, the black levels seem to be getting output as limited RGB instead of full RGB (0-255) without any way to change it. This would be a minor annoyance if my TV detected it as limited RGB and properly adjusted, but it doesn't. I'm not sure if this is the fault of the TV (Panasonic plasma), or the Android TV device, or what.

Has anyone else had these issues? Besides these annoyances, I'm really enjoying my purchase!

JimboLodisC

Did you do all the software updates? I think one of the recent patches fixed washed out colors. That might be what you're experiencing.

bigduffeye

i have a yamaha amp connected to my shield via hdmi.

cec works as i can use the amps remote to control the shield, however when i turn on the cec volume control in settings it will not adjust the volume of the amp when i use the shield remote control.

this is an nvidia issue. when in plex and i try to adjust volume i get a toast notification on the screen saying the volume is set for surround sound and to use the remote for my receiver. this tells me that the shield isnt going into cec mode properly.

post about it on the nvidia forums

https://forums.geforce.com/default/topic/884759/shield-android-tv/hdmi-cec-problems/

3rob3

No HDMI-CEC volume control here either. As far as I have been able to find it is a known bug and I haven't seen anyone who has it working. I am really hoping this is fixed in the upcoming update.

ChaseMe3

I too have a Panasonic Plasma, and noticed the image quality is lacking on the Shield compared to my HTPC (Intel NUC). So all my HQ content (movies, tv series etc) I still watch on the HTPC with Kodi. Kinda sucks, I'd love to repurpose the HTPC but it really bothers me when blacks are dark grey in everything on the Shield.

silverownz

I also have issues with CEC volume controls on my TV (Vizio M-Series with a Vizio Sound bar). I contacted support and they were mostly unhelpful. Finally I looked into the issue myself to see what was up. Here's what I wrote up to nvidia support after my testing:

I did some digging around and found some useful information about how my system handles CEC messages. Thus far, I haven't been able to get my TV itself to recognize volume control messages, but instead, my audio system recognizes them and processes them correctly.

Here is what my setup looks like: I have the M70-C3 Vizio tv with the Nvidia shield directly connected to it via HDMI. I also have a Vizio 5.1 sound system (S5451w-C2) connected to the tv via HDMI.

In order to test my system with CEC messages, I used a RaspberryPi 2 connected to my tv via HDMI. I installed cec-client on my Pi, which makes use of libCEC ( http://manpages.ubuntu.com/manpages/trusty/man1/cec-client.1.html ). With cec-client running, I am able to send the following commands to my system: "tx 15:44:41" (volume up to audio system) and "tx 15:44:42" (volume down to audio system). Issuing these commands worked exactly as expected. My 5.1 audio system adjusted its volume accordingly, which is ultimately the result I am looking for. Since I was able to get the desired functionality with my Pi, I'm quite sure the Shield is also capable. Might I suggest that this is a limitation/bug that ought to be addressed? I believe many audio receivers support CEC, so being able to control them from the Shield makes sense. Also, if what you said earlier is true (about few TVs supporting CEC audio control functions), then a plausible workaround is controlling the audio system directly.

Here is why this is very important to me. When using applications such as Plex or Kodi, there are many times when the 5.1 dts or dolby audio signal is set to passthrough. When this is the case, the Shield cannot modify the signal at all, otherwise, distortion will occur. When the Shield is set to 'Variable audio control' and audio is being passed through the shield to the audio system, any changes to audio levels completely distorts the sound and is essentially unusable. Using CEC to control volume is the only way around this. Of course, I can always carry around a second remote solely to control volume, but that is not why I purchased an Nvidia remote in the first place :)

Please let me know if this is something that could possibly be fixed in future patches or if you need any additional information from me.

It's quite possible that your TV just doesn't support it. If you're savvy enough, you could try doing what I did with a linux device that has proper hdmi ports (raspberry pi being one) to test out how your TV responds to CEC commands.

I've been quite disappointed with this lack of functionality from the Shield.