I refused to pay stupid prices for another Remote base station after my power supply seemed to get to the point where it couldn't supply enough current to charge the battery. I found THIS option:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

... allowing me to CUT THE CABLE and add a USB 2 connector as the charging option. As long as I have a 5V 2A supply, which many USB chargers are capable of, I can now charge my Duet Remote without issue. Other users have opted to get another 5V 2A wired supply and 'splice' the cable... I'd rather do this as it gives my MULTIPLE options as supplies die off.

All this time I thought it was bad batteries, and it ended up being the power supply not being able to supply enough current to keep the batteries alive.

BTW, the USB connectors are labeled with +/- for power with the other three terminals for data. EASY HOOK UP!!