There are a couple of bugs in the Plex Android TV app or Android TV you might run across.
Seamless Branching: This has to do with how different cuts of a movie are stitched together on a blu-ray disc. I’ve run into it on a couple of 4K HDR rips, usually on an extended release / director’s cut. When you hit the bug, the audio will noticeably go out of sync with the video. You have to stop (not pause), then restart playback . Best I can tell, it requires a fix for Exoplayer, the Android TV video player (a Google, not Plex fix). There are several threads on the topic, such as this one.
There is another bug where VOBSUB subtitles, the kind found on DVDs, do not render correctly. They are incorrectly positioned on the screen and may not be completely visible. I’ve very little media with VOBSUB, so not sure if this bug still exists.
Other Shield Limitations
I use the Plex and You Tube TV apps on my Shield. Rarely any others. Both of those apps work very well.
I’ve the 2015 Shield, which does not support Dolby Vision. As a result, I still use the Netflix & Amazon apps on the LG.
Denon
Take the time to use the microphone and perform the audio setup. It made a noticeable difference on my system.
I have all the video processing turned off in the Denon. I let the TV perform any necessary upscaling, etc. I’ve played around with the settings and can’t really tell that much difference with them enabled/disabled.
The 2015 Shield does not have the AI Upscaling capability like the 2019 version, so not sure how that comes into play.
Basically, experiment and use what you like best.
LG
Connect the Denon to the HDMI-ARC/eARC input on the LG TV.
Check the LG’s settings for that input. Make sure it has a wide color-gamut. It should configure that automatically, but never hurts to check. Note: This is on my B7, which is several years older and running an older version of webOS. I don’t know if that setting exists on current LG TVs.
One Remote
You can configure the TV/receiver/Shield to power each other on/off, control volume, etc. It is part of the HDMI specification (HDMI-CEC = Consumer Electronics Control), and has been available for several years.
I press the power button on the Shield. It powers on the Shield, Denon, & LG. It also switches the Denon and LG to the correct inputs. I press it again and everything powers off. The power button on the LG remote does the same.
Volume up/down on the LG remote (or TV remote) controls volume on the Denon.
I have not tried using the LG remote to control the Shield - switching apps, etc. In theory it is possible.
On the LG B7 it is configured in Settings → General → Simplink. Two options. First enables the feature. The second enables Auto Power Sync. I’ve both enabled.
Denon: Configured in Video → HDMI options. HDMI Control = On. There are some other options you can configure to fine tune things.
Shield: Settings → Display & Sound → Power Control. Several options about how the Shield should behave. Probably start with all enabled, then fine tune as needed.
