rx-player: INCOMPATIBLE_KEYSYSTEMS error using DASH/Widevine on Panasonic 2019

When testing RxPlayer (version 3.29.0) on a Panasonic 2019 model, I encountered the following error while trying to play a DASH/Widevine stream:

EncryptedMediaError (INCOMPATIBLE_KEYSYSTEMS) No key system compatible with your wanted configuration has been found in the current browser

Sample code:

player.loadVideo({
    transport: "dash",
    url: [redacted].index.mpd,
    keySystems: [
        {
            type: "widevine",
            getLicense: function(message) { ... },
            getLicenseConfig: {
                retry: 5,
                timeout: 30000,
            },
            fallbackOn: {
                keyInternalError: true,
                keyOutputRestricted: true,
            },
            disableMediaKeysAttachmentLock: true,
            closeSessionsOnStop: true,
            serverCertificate: ...
        }
    ],
    autoPlay: true,
    startAt: undefined,
    enableFastSwitching: "false",
    onCodecSwitch: "reload",
    textTrackMode: "html",
    textTrackElement: document.CreateElement("div"),
});

When checking the same stream with Shaka Player, playback can be started without issues. So, at first glance it appears that the TV should support the supplied source & that RxPlayer incorrectly throws this error message.