Hey Sonos support, please note that the string table for PowerApp has invalid xml in it. Specifically this:

<?xml version="1.0" encoding="UTF-8"?>
<!--rev numbers are to be ignored, and should not be used.-->
<stringtables xmlns="http://sonos.com/sonosapi">
<stringtable rev="1" xml:lang="en-US">
    <string stringId="ServicePromo">PowerApp - Unlimited Music & Video</string>
    <string stringId="Button_Register">Sign up For PowerApp</string>
    <string stringId="Button_Login">I already have an account</string>
    <string stringId="Error5Message">Access token not found, retry</string>
</stringtable>
<stringtable rev="1" xml:lang="da-DK">
    <string stringId="ServicePromo">PowerApp - Unlimited Music & Video</string>
    <string stringId="Button_Register">Sign up For PowerApp</string>
    <string stringId="Button_Login">I already have an account</string>
    <string stringId="Error5Message">Access token not found, retry</string>

Note that it is not valid to have unescaped “&”s in xml. Please reach out to your service team that generates these from PowerApp’s submission to be sure to escape them all property.

The full file is hosted by Sonos here:

https://cf.ws.sonos.com/p/s/449f2e9a-2644-4dbf-925c-6e862b1afc5e