I got my BT-3400 v. 2.2 from ‘rdana’ on Ebay and the adapter would choke on anything over 700mA*4. Richard sent me another one but it was 2A and then he sent me a 3rd, which does 3A and it works fine.

In the interim, I bought one of the 12v LITE-ON bricks that puts out 5.5A and while the inner ‘+’ hole in the barrel connector is slightly ‘over-sized,’ it still works if I don’t move the connector while charging. This brand was recommended buy GAUSS163, as being robust.

The part number is ‘PA-1660-2SA1’ and it has a typical IEC connector for PCs and it takes up to 240v, so variable in that regard.

Chris