No, you say the same enclosure works fine with a 2TB drive and the Live/Live Plus. That immediately points to an MBR/GPT issue of one kind or another.
Many enclosures weren’t designed to originally work with large drives, and support for GPT was added after-the-fact.
So, if the enlcosure(s) has(have) loaded a driver on the PC to enable it to use GPT drives, then with no way to load the same driver onto other devices, that enclosure simply will not be usable with a GPT drive on _ anything _ that can’t load the driver, be it a media player or a printer or a TV or a BluRay player. It wouldn’t need drivers for smaller drives.
That’s why I suggested connecting the enclosure(s) with a 3TB drive inside, to another device other than an actual PC or a WDTV.
Because, other than asking the manufacturer for confirmation that it will work with 3TB drives with other non-PC devices, that’s about all that can be done to try and figure out where the conflict lies.
But, if you don’t need to do any of that, then there’s not really anything else anyone can do to try and help.
