Apparently, Anker batteries often don’t support 12v. They’ll do 5 or 6, 9, 15, 18… but not 12. I tried with one (and the Birdcord PD12v) and could power my OT, but not my AR or ST. Changed the powerbank to the Baseus one Songbird recommend and it’s been brilliant.
(Oh… I read further down the thread and this has already been discussed. Sorry).