>Your profile may be set to 'Adaptive', and it may automatically use the 'Primarily AC' behavior. Initially, it was set to Adaptive by default in the BIOS. Dur

>Your profile may be set to 'Adaptive', and it may automatically use the 'Primarily AC' behavior. Initially, it was set to Adaptive by default in the BIOS. During the process of fault-finding -- changed it to 'Standard' hoping that the firmware will relinquish control and give it back to the OS, allowing it to over-ride any settings. I have toggled settings for power management where you can choose the mode of charging, to prolong battery life i.e. constant power or restricted to certain levels, schedules etc., without any joy. I have reset the BIOS a couple of times, but will try all your suggested solutions from scratch, including installing the Dell Power Manager ─ something I have not tried before ─ to see where it leads. Thanks for your continued patience. I will let you know what happens, regardless of the outcome.