XPS 18 (1810) not charging when running

Hi,

i now also have a charging - issue on my 2nd XPS18, but this time a different one:

Side and stand-power sockets are both working.

Installed a new battery because the old one only had 35% left.

Started to work fine but after 2 days XPS reports - when Win10 (64bit) is running: "plugged in, not charging"

When XPS is shut down Battery will Charge 99%-100% full (both sockets).

Tried all usual stuff as uninstalling "Microsoft ACPI-Compliant Control Method Battery", etc.

powercfg /batteryreport  says battery is 100% fine

BIOS (A10) reports 65W AC Adapter Type and "This battery is performing normally.

Any ideas people of DELL ?