DYS Gopro Smart 3 Axis power problems??

[Rocket_Col]

Help needed please. I have a DYS Smart 3 axis gimbal.
All ok, done what says on a few sites. Set PID etc. and almost there just needs tweaks.
It all runs fine with battery and USB connected (through a 12v bec)
BUt, if you remove the USB it seems way under powered as if there is not enough power to keep camera in correct position. The camera tilt from my TX also does not work, but does with the usb in??
Think there is a power problem somewhere?
Ideas please...

[powerlord]

There is a very active Facebook group you might wanna join.  Maybe check the output of your bec?

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