I’m currently also experiencing this issue. Having the Plex App on my Panasonic TV there seems to be some sort of built-in limitation for 4 Mbps Bitrate (see below name=video.bitrate&value=4000).
I already configured in the settings the Quality for local and remote servers to “Original”. The plex server is in the same network as the client (Panasonic HZW1504) though.
Log from the server
Dec 28, 2021 11:09:43.194 [0x7fcea3d5ab38] Debug — Request: [192.168.1.121:41874 (Allowed Network (Subnet))] GET /video/:/transcode/universal/decision?directPlay=0&directStream=1&directStreamAudio=0&protocol=dash&fastSeek=1&path=%2Flibrary%2Fmetadata%2F1813&session=xxxx&mediaIndex=0&partIndex=0&mediaBufferSize=50000&hasMDE=1&subtitleSize=100&videoQuality=100&videoResolution=1920x1080&audioBoost=100&location=lan (9 live) GZIP Signed-in Token (abc@abc.abc) / Accept => application/json / Accept-Encoding => gzip, deflate / Accept-Language => de / Connection => keep-alive / Host => 192.168.1.100:32400 / Origin => https://app.plex.tv / User-Agent => HbbTV/1.4.1 (;Panasonic;VIERA 2020;3.669;0501-0003 0000-0100;) PanasonicSDK/2017 / X-Plex-Client-Identifier => irbb8ieynq08p0prwh52ke29 / X-Plex-Client-Profile-Extra => add-transcode-target(type=videoProfile&context=streaming&protocol=dash&container=mp4&videoCodec=h264&audioCodec=aac)+add-limitation(scope=videoAudioCodec&scopeName=aac&type=upperBound&name=audio.channels&value=2)+add-limitation(scope=videoTranscodeTarget&scopeName=h264&scopeType=videoCodec&context=streaming&protocol=dash&type=upperBound&name=video.bitDepth&value=8)+add-limitation(scope=videoTranscodeTarget&scopeName=h264&scopeType=videoCodec&context=streaming&protocol=dash&type=upperBound&name=video.bitrate&value=4000)+add-limitation(scope=videoAudioCodec&scopeName=h264&scopeType=videoCodec&context=streaming&protocol=dash&type=match&name=video.orientation&list=0)+add-limitation(scope=videoTranscodeTarget&scopeName=h264&scopeType=videoCodec&context=streaming&protocol=dash&type=upperBound&name=video.width&value=1920)+add-limitation(scope=videoTranscodeTarget&scopeName=h264&scopeType=videoCodec&context=streaming&protocol=dash&type=upperBound&name=video.height&value=1080)+add-limitation(scope=videoCodec&scopeName=h264&type=upperBound&name=video.level&value=50) / X-Plex-Client-Profile-Name => Generic / X-Plex-Device => Generic - panasonic / X-Plex-Device-Name => Generic / X-Plex-Device-Screen-Resolution => 1920x1080 / X-Plex-Device-Vendor => Unknown / X-Plex-Drm => widevine:video / X-Plex-Features => external-media,indirect-media / X-Plex-Language => de / X-Plex-Model => Gecko / X-Plex-Platform => panasonic / X-Plex-Platform-Version => Unknown / X-Plex-Product => Plex for Smart TVs / X-Plex-Token => xxxxxxxxxxxxxxxxxxxx / X-Plex-Version => 5.29.1
